Introduction

The following are the events for the OpenJDK 20 (jdk-20+30, 22-January-2023). The events are collected from the event configuration and the source code. Visit jfreventcollector for more information. this is also the place you can contribute additional event descriptions, if you don't want to contribute them directly to the OpenJDK. The site generator lives on GitHub too.

This page is maintained by Johannes Bechberger of the SapMachine team at SAP and contributors.

Flight Recorder

DumpReason

default profiling startTime 11 17 20 21

Category: Flight Recorder

Who requested the recording and why

Configuration enabled
default true
profiling true

Field Type Description
reason string Reason Reason for writing recording data to disk
recordingId int Recording Id Id of the recording that triggered the dump, or -1 if it was not related to a recording

DataLoss

default profiling startTime 11 17 20 21

Category: Flight Recorder

Data could not be copied out from a buffer, typically because of contention

Configuration enabled
default true
profiling true

Field Type Description
amount ulong: bytes Amount Amount lost data
total ulong: bytes Total Total lost amount for thread

Examples 3
amount ulong: bytes
16356
startTime long: millis
536810060125
total ulong: bytes
1734053
amount ulong: bytes
16356
startTime long: millis
432711947167
total ulong: bytes
1292348
amount ulong: bytes
16356
startTime long: millis
498062293667
total ulong: bytes
359883

Flush

experimental startTime duration 14 17 20 21

Category: Flight Recorder

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled threshold
default false 0 ns
profiling false 0 ns

Field Type Description
flushId ulong Flush Identifier
elements ulong Elements Written
size ulong: bytes Size Written

Examples 3
elements ulong
1392
flushId ulong
221
size ulong: bytes
219631
startTime long: millis
494882403542
elements ulong
3720
flushId ulong
174
size ulong: bytes
1443194
startTime long: millis
497906124792
elements ulong
11514
flushId ulong
333
size ulong: bytes
2128133
startTime long: millis
584064483625

ActiveRecording

default profiling startTime duration stackTrace 11 17 20 21

Source src/jdk.jfr/share/classes/jdk/jfr/events/ActiveRecordingEvent.java

Category: Flight Recorder

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
id long Id
name string Name Consider contributing a description to jfreventcollector.
destination string Destination Consider contributing a description to jfreventcollector.
maxAge long: millis Max Age
flushInterval long: millis 14+ Flush Interval
maxSize long: bytes Max Size
recordingStart long: epochmillis Start Time
recordingDuration long: millis Recording Duration

Examples 3
destination string
[...]/code/experiments/jfreventcollector/jfr/sample_UseSerialGC.jfr
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1673458608832
stackTrace StackTrace
null
startTime long: millis
357238083
destination string
[...]/code/experiments/jfreventcollector/jfr/sample_UseG1GC.jfr
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1673457379057
stackTrace StackTrace
null
startTime long: millis
333187834
destination string
[...]/code/experiments/jfreventcollector/jfr/sample_UseParallelGC.jfr
flushInterval long: millis
1000
id long
1
maxAge long: millis
9223372036854775807
maxSize long: bytes
262144000
name string
1
recordingDuration long: millis
9223372036854775807
recordingStart long: epochmillis
1673458001344
stackTrace StackTrace
null
startTime long: millis
376195834

ActiveSetting

default profiling startTime duration stackTrace 11 17 20 21

Source src/jdk.jfr/share/classes/jdk/jfr/events/ActiveSettingEvent.java

Category: Flight Recorder

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
id long Event Id
name string Setting Name
value string Setting Value

Examples 3
id long
94
name string
period
stackTrace StackTrace
null
startTime long: millis
476715963750
value string
beginChunk
id long
1730
name string
period
stackTrace StackTrace
null
startTime long: millis
483203615292
value string
beginChunk
id long
52
name string
enabled
stackTrace StackTrace
null
startTime long: millis
381379409250
value string
true

JVM

JVMInformation

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine

Description of JVM and the Java application

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
jvmName string JVM Name
jvmVersion string JVM Version
jvmArguments string JVM Command Line Arguments
jvmFlags string JVM Settings File Arguments
javaArguments string Java Application Arguments
jvmStartTime long: epochmillis JVM Start Time
pid long Process Identifier

Examples 3
javaArguments string
[...]/code/experiments/jfreventcollector/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=[...]/code/experiments/jfreventcollector/jfr/sample_UseG1GC.jfr,settings=[...]/code/experiments/jfreventcollector/.cache/jfc.jfc -XX:+UseG1GC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1673457378757
jvmVersion string
OpenJDK 64-Bit Server VM (19+36-sapmachine) for bsd-aarch64 JRE (19+36-sapmachine), built on Sep 19 2022 15:20:37 by "apurple" with clang Apple LLVM 13.0.0 (clang-1300.0.29.3)
pid long
59413
startTime long: millis
577715906959
javaArguments string
[...]/code/experiments/jfreventcollector/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=[...]/code/experiments/jfreventcollector/jfr/sample_UseParallelGC.jfr,settings=[...]/code/experiments/jfreventcollector/.cache/jfc.jfc -XX:+UseParallelGC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1673458001022
jvmVersion string
OpenJDK 64-Bit Server VM (19+36-sapmachine) for bsd-aarch64 JRE (19+36-sapmachine), built on Sep 19 2022 15:20:37 by "apurple" with clang Apple LLVM 13.0.0 (clang-1300.0.29.3)
pid long
59959
startTime long: millis
567895398709
javaArguments string
[...]/code/experiments/jfreventcollector/.cache/renaissance.jar -t 5 -r 1 all
jvmArguments string
-XX:StartFlightRecording=filename=[...]/code/experiments/jfreventcollector/jfr/sample_UseSerialGC.jfr,settings=[...]/code/experiments/jfreventcollector/.cache/jfc.jfc -XX:+UseSerialGC
jvmFlags string
null
jvmName string
OpenJDK 64-Bit Server VM
jvmStartTime long: epochmillis
1673458608531
jvmVersion string
OpenJDK 64-Bit Server VM (19+36-sapmachine) for bsd-aarch64 JRE (19+36-sapmachine), built on Sep 19 2022 15:20:37 by "apurple" with clang Apple LLVM 13.0.0 (clang-1300.0.29.3)
pid long
60548
startTime long: millis
400832823750

InitialSystemProperty

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine

System Property at JVM start

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
key string Key
value string Value

Examples 3
key string
java.vm.compressedOopsMode
startTime long: millis
390596682542
value string
Zero based
key string
jdk.debug
startTime long: millis
487872223500
value string
release
key string
sun.boot.library.path
startTime long: millis
521828620459
value string
[...]/.sdkman/candidates/java/19-sapmchn/lib

JVM: Class Loading

ClassLoad

startTime duration eventThread stackTrace 11 17 20 21

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled stackTrace threshold
default false true 0 ms
profiling false true 0 ms

Field Type Description
loadedClass Class Loaded Class Consider contributing a description to jfreventcollector.
definingClassLoader ClassLoader Defining Class Loader Consider contributing a description to jfreventcollector.
initiatingClassLoader ClassLoader Initiating Class Loader Consider contributing a description to jfreventcollector.

Examples 3
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
initiatingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
loadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
true
modifiers int
4144
name string
org.apache.spark.storage.BlockManagerMasterEndpoint$$Lambda$18844+0x000000080422f678/698234711
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/storage
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1057
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
445002838792
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
48
name string
java.lang.invoke.LambdaForm$MH+0x000000080024b000/1132410754
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang/invoke
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1057
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
type FrameType
Native
truncated boolean
true
startTime long: millis
484132731125
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
48
name string
java.lang.invoke.LambdaForm$MH+0x00000008041fc000/1281211198
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang/invoke
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1057
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
type FrameType
Native
truncated boolean
true
startTime long: millis
502812353209

ClassDefine

startTime eventThread stackTrace 11 17 20 21

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
definedClass Class Defined Class Consider contributing a description to jfreventcollector.
definingClassLoader ClassLoader Defining Class Loader Consider contributing a description to jfreventcollector.

Examples 3
definedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
49
name string
org/apache/spark/ml/recommendation/ALSModel$$typecreator25$1
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/ml/recommendation
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1057
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
553833300084
definedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
49
name string
org/apache/spark/scheduler/StopCoordinator$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/scheduler
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1057
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
450397774208
definedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
49
name string
scala/reflect/internal/tpe/TypeConstraints$UndoPair
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect/internal/tpe
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/String;[BIILjava/security/ProtectionDomain;Ljava/lang/String;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass1
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1057
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
type FrameType
Native
truncated boolean
true
startTime long: millis
537874062084

ClassRedefinition

default profiling startTime 15 17 20 21

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
redefinedClass Class Redefined Class Consider contributing a description to jfreventcollector.
classModificationCount int Class Modification Count The number of times the class has changed
redefinitionId ulong Class Redefinition Id

RedefineClasses

default profiling startTime duration eventThread stackTrace 15 17 20 21

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled stackTrace threshold
default true true 0 ms
profiling true true 0 ms

Field Type Description
classCount int Class Count
redefinitionId ulong Class Redefinition Id

RetransformClasses

default profiling startTime duration eventThread stackTrace 15 17 20 21

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled stackTrace threshold
default true true 0 ms
profiling true true 0 ms

Field Type Description
classCount int Class Count
redefinitionId ulong Class Redefinition Id

ClassUnload

startTime eventThread 11 17 20 21

Category: Java Virtual Machine / Class Loading

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default false
profiling false

Field Type Description
unloadedClass Class Unloaded Class Consider contributing a description to jfreventcollector.
definingClassLoader ClassLoader Defining Class Loader Consider contributing a description to jfreventcollector.

Examples 3
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
startTime long: millis
454506558583
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
true
modifiers int
4144
name string
org.renaissance.jdk.streams.MnemonicsCoderWithStream$$Lambda$18982+0x0000000804270c60/1698222583
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
org/renaissance/jdk/streams
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
startTime long: millis
543927242459
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
1057
name string
scala/collection/mutable/AbstractMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/mutable
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
startTime long: millis
559700714667
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
33
name string
scala/collection/mutable/HashMap
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection/mutable

JVM: Code Cache

CodeCacheFull

default profiling startTime eventThread 11 17 20 21

Category: Java Virtual Machine / Code Cache

A code heap is full, this leads to disabling the compiler

Configuration enabled
default true
profiling true

Field Type Description
codeBlobType CodeBlobType Code Heap Consider contributing a description to jfreventcollector.
startAddress ulong: address Start Address
commitedTopAddress ulong: address Commited Top
reservedTopAddress ulong: address Reserved Top
entryCount int Entries
methodCount int Methods
adaptorCount int Adaptors
unallocatedCapacity ulong: bytes Unallocated
fullCount int Full Count
codeCacheMaxCapacity ulong: bytes 17+ Code Cache Maximum Capacity

CodeCacheStatistics

default profiling startTime every chunk 11 17 20 21

Category: Java Virtual Machine / Code Cache

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true everyChunk
profiling true everyChunk

Field Type Description
codeBlobType CodeBlobType Code Heap Consider contributing a description to jfreventcollector.
startAddress ulong: address Start Address
reservedTopAddress ulong: address Reserved Top
entryCount int Entries
methodCount int Methods
adaptorCount int Adaptors
unallocatedCapacity ulong: bytes Unallocated
fullCount int Full Count

Examples 3
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'non-profiled nmethods'
entryCount int
18537
fullCount int
0
methodCount int
18537
reservedTopAddress ulong: address
5754585088
startAddress ulong: address
5631672320
startTime long: millis
507460804542
unallocatedCapacity ulong: bytes
85971328
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'non-profiled nmethods'
entryCount int
18294
fullCount int
0
methodCount int
18294
reservedTopAddress ulong: address
5351931904
startAddress ulong: address
5229019136
startTime long: millis
406109152917
unallocatedCapacity ulong: bytes
86969088
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'profiled nmethods'
entryCount int
21397
fullCount int
0
methodCount int
21396
reservedTopAddress ulong: address
5232672768
startAddress ulong: address
5109776384
startTime long: millis
535482580792
unallocatedCapacity ulong: bytes
60447872

CodeCacheConfiguration

default profiling startTime end chunk 11 17 20 21

Category: Java Virtual Machine / Code Cache

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
initialSize ulong: bytes Initial Size
reservedSize ulong: bytes Reserved Size
nonNMethodSize ulong: bytes Non-nmethod Size
profiledSize ulong: bytes Profiled Size
nonProfiledSize ulong: bytes Non-profiled Size
expansionSize ulong: bytes Expansion size
minBlockLength ulong: bytes Minimum Block Length
startAddress ulong: address Start Address
reservedTopAddress ulong: address Reserved Top

Examples 3
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5839564
nonProfiledSize ulong: bytes
122909338
profiledSize ulong: bytes
122909338
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
5351931904
startAddress ulong: address
5100273664
startTime long: millis
468522477958
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5839564
nonProfiledSize ulong: bytes
122909338
profiledSize ulong: bytes
122909338
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
5754585088
startAddress ulong: address
5502926848
startTime long: millis
535419011667
expansionSize ulong: bytes
65536
initialSize ulong: bytes
2555904
minBlockLength ulong: bytes
6
nonNMethodSize ulong: bytes
5839564
nonProfiledSize ulong: bytes
122909338
profiledSize ulong: bytes
122909338
reservedSize ulong: bytes
251658240
reservedTopAddress ulong: address
5361434624
startAddress ulong: address
5109776384
startTime long: millis
588922519625

JVM: Compiler

JITRestart

default profiling startTime eventThread 17 20 21

Category: Java Virtual Machine / Compiler

Restart of the JIT compilers after they were stopped

Configuration enabled
default true
profiling true

Field Type Description
freedMemory ulong: bytes Freed Memory
codeCacheMaxCapacity ulong: bytes Code Cache Maximum Capacity

Compilation

default profiling startTime duration eventThread 11 17 20 21

Category: Java Virtual Machine / Compiler

Results of method compilation attempts

Configuration enabled threshold
default true 1000 ms
profiling true 100 ms

Field Type Description
compileId uint Compilation Identifier
compiler CompilerType 14+ Compiler Consider contributing a description to jfreventcollector.
method Method Method Consider contributing a description to jfreventcollector.
compileLevel ushort Compilation Level
succeded boolean Succeeded
isOsr boolean On Stack Replacement
codeSize ulong: bytes Compiled Code Size
inlinedBytes ulong: bytes Inlined Code Size

Examples 3
codeSize ulong: bytes
1792
compileId uint
60343
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
50
isOsr boolean
false
method Method
descriptor string
(Lorg/apache/spark/serializer/SerializerInstance;)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
value
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
33
name string
org/apache/spark/scheduler/DirectTaskResult
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/scheduler
startTime long: millis
552412436792
succeded boolean
true
codeSize ulong: bytes
21840
compileId uint
78687
compileLevel ushort
4
compiler CompilerType
c2
inlinedBytes ulong: bytes
5091
isOsr boolean
false
method Method
descriptor string
(Ldotty/tools/dotc/ast/Trees$Tree;Ldotty/tools/dotc/core/Types$Type;Ldotty/tools/dotc/util/SimpleIdentitySet;ZLdotty/tools/dotc/core/Contexts$Context;)Ldotty/tools/dotc/ast/Trees$Tree;
hidden boolean
false
modifiers int
2
name string
adapt1
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
33
name string
dotty/tools/dotc/typer/Typer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
dotty/tools/dotc/typer
startTime long: millis
585220811000
succeded boolean
true
codeSize ulong: bytes
856
compileId uint
60022
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
26
isOsr boolean
false
method Method
descriptor string
(Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
true
modifiers int
1
name string
apply
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
true
modifiers int
4144
name string
org.apache.spark.rdd.PairRDDFunctions$$Lambda$18823+0x000000080420ca00/1974559220
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/rdd
startTime long: millis
441007016875
succeded boolean
true

CompilerPhase

default profiling startTime duration eventThread 11 17 20 21

Category: Java Virtual Machine / Compiler

Describes various phases of the compilation process like inlining or string optimization related phases

Configuration enabled threshold
default true 60 s
profiling true 10 s

Field Type Description
phase CompilerPhaseType Compile Phase
compileId uint Compilation Identifier
phaseLevel ushort Phase Level

CompilationFailure

profiling startTime eventThread 11 17 20 21

Category: Java Virtual Machine / Compiler

In case a JIT compilation failed, a compilation failure is triggered, reporting the reason

Configuration enabled
default false
profiling true

Field Type Description
failureMessage string Failure Message
compileId uint Compilation Identifier

Examples 3
compileId uint
74914
failureMessage string
concurrent class loading
startTime long: millis
586349228834
compileId uint
81826
failureMessage string
concurrent class loading
startTime long: millis
489027337167
compileId uint
74929
failureMessage string
concurrent class loading
startTime long: millis
583286002875

CompilerInlining

startTime eventThread 11 17 20 21

Category: Java Virtual Machine / Compiler / Optimization

Describes the result of a method inlining attempt

Configuration enabled
default false
profiling false

Field Type Description
compileId uint Compilation Identifier
caller Method Caller Method
callee CalleeMethod struct Callee Method
succeeded boolean Succeeded
message string Message
bci int Bytecode Index

Examples 3
bci int
44
callee CalleeMethod
descriptor string
()Lorg/apache/spark/status/api/v1/TaskMetrics;
name string
metrics
type string
org/apache/spark/status/LiveTask
caller Method
descriptor string
()Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
doUpdate
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
33
name string
org/apache/spark/status/LiveTask
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/status
compileId uint
59252
message string
inline
startTime long: millis
476713453292
succeeded boolean
true
bci int
43
callee CalleeMethod
descriptor string
()Lorg/apache/spark/util/AccumulatorMetadata;
name string
metadata
type string
org/apache/spark/util/AccumulatorV2
caller Method
descriptor string
(Lorg/apache/spark/executor/TaskMetrics;Lorg/apache/spark/util/AccumulatorV2;)Ljava/lang/Object;
hidden boolean
false
modifiers int
4121
name string
$anonfun$fromAccumulators$1
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
49
name string
org/apache/spark/executor/TaskMetrics$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/executor
compileId uint
59185
message string
inline
startTime long: millis
381397819083
succeeded boolean
true
bci int
26
callee CalleeMethod
descriptor string
(Ljava/util/function/IntConsumer;)Z
name string
tryAdvance
type string
java/lang/StringUTF16$CharsSpliterator
caller Method
descriptor string
(Ljava/util/Spliterator;Ljava/util/stream/Sink;)Z
hidden boolean
false
modifiers int
16
name string
forEachWithCancel
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1056
name string
java/util/stream/IntPipeline
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/util/stream
compileId uint
58956
message string
inline (hot)
startTime long: millis
483204389792
succeeded boolean
true

Deoptimization

default profiling startTime eventThread stackTrace 14 17 20 21

Category: Java Virtual Machine / Compiler

Describes the detection of an uncommon situation in a compiled method which may lead to deoptimization of the method

Configuration enabled stackTrace
default true false
profiling true true

Field Type Description
compileId uint Compilation Identifier
compiler CompilerType Compiler Consider contributing a description to jfreventcollector.
method Method Method Consider contributing a description to jfreventcollector.
lineNumber int Line Number
bci int Bytecode Index
instruction Bytecode Instruction Consider contributing a description to jfreventcollector.
reason DeoptimizationReason Reason Consider contributing a description to jfreventcollector.
action DeoptimizationAction Action Consider contributing a description to jfreventcollector.

Examples 3
action DeoptimizationAction
maybe_recompile
bci int
70
compileId uint
60308
compiler CompilerType
c2
instruction Bytecode
invokeinterface
lineNumber int
738
method Method
descriptor string
(Lscala/Function2;)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
reduceLeft
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
1537
name string
scala/collection/IterableOnceOps
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection
reason DeoptimizationReason
bimorphic_or_optimized_type_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
70
lineNumber int
738
method Method
descriptor string
(Lscala/Function2;)Ljava/lang/Object;
hidden boolean
false
modifiers int
1
name string
reduceLeft
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
1537
name string
scala/collection/IterableOnceOps
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
scala/collection
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
450150930458
action DeoptimizationAction
maybe_recompile
bci int
1
compileId uint
40866
compiler CompilerType
c2
instruction Bytecode
checkcast
lineNumber int
-1
method Method
descriptor string
(ILjava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
true
modifiers int
8
name string
linkToTargetMethod
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
48
name string
java/lang/invoke/Invokers$Holder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang/invoke
reason DeoptimizationReason
speculate_class_check
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
1
lineNumber int
-1
method Method
descriptor string
(ILjava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
hidden boolean
true
modifiers int
8
name string
linkToTargetMethod
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
48
name string
java/lang/invoke/Invokers$Holder
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang/invoke
type FrameType
JIT compiled
truncated boolean
true
startTime long: millis
562693384500
action DeoptimizationAction
reinterpret
bci int
6
compileId uint
41590
compiler CompilerType
c2
instruction Bytecode
ifnull
lineNumber int
1185
method Method
descriptor string
()Z
hidden boolean
false
modifiers int
16
name string
apparentlyFirstQueuedIsExclusive
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1057
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/util/concurrent/locks
reason DeoptimizationReason
unstable_if
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
6
lineNumber int
1185
method Method
descriptor string
()Z
hidden boolean
false
modifiers int
16
name string
apparentlyFirstQueuedIsExclusive
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1057
name string
java/util/concurrent/locks/AbstractQueuedSynchronizer
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/util/concurrent/locks
type FrameType
Inlined
truncated boolean
false
startTime long: millis
544248083084

CompilerStatistics

default profiling startTime every chunk 11 17 20 21

Category: Java Virtual Machine / Compiler

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true 1000 ms
profiling true 1000 ms

Field Type Description
compileCount int Compiled Methods
bailoutCount int Bailouts
invalidatedCount int Invalidated Compilations
osrCompileCount int OSR Compilations
standardCompileCount int Standard Compilations
osrBytesCompiled ulong: bytes OSR Bytes Compiled
standardBytesCompiled ulong: bytes Standard Bytes Compiled
nmethodsSize ulong: bytes Compilation Resulting Size
nmethodCodeSize ulong: bytes Compilation Resulting Code Size
peakTimeSpent long: millis Peak Time
totalTimeSpent long: millis Total time

Examples 3
bailoutCount int
10
compileCount int
56313
invalidatedCount int
0
nmethodCodeSize ulong: bytes
69933824
nmethodsSize ulong: bytes
113098744
osrBytesCompiled ulong: bytes
0
osrCompileCount int
621
peakTimeSpent long: millis
9368
standardBytesCompiled ulong: bytes
0
standardCompileCount int
55692
startTime long: millis
450765996083
totalTimeSpent long: millis
507552
bailoutCount int
8
compileCount int
55497
invalidatedCount int
0
nmethodCodeSize ulong: bytes
73751616
nmethodsSize ulong: bytes
115417800
osrBytesCompiled ulong: bytes
0
osrCompileCount int
605
peakTimeSpent long: millis
19331
standardBytesCompiled ulong: bytes
0
standardCompileCount int
54892
startTime long: millis
507758398042
totalTimeSpent long: millis
415324
bailoutCount int
10
compileCount int
59430
invalidatedCount int
0
nmethodCodeSize ulong: bytes
74046720
nmethodsSize ulong: bytes
118757704
osrBytesCompiled ulong: bytes
0
osrCompileCount int
623
peakTimeSpent long: millis
20643
standardBytesCompiled ulong: bytes
0
standardCompileCount int
58807
startTime long: millis
569139098875
totalTimeSpent long: millis
748817

CompilerConfiguration

default profiling startTime end chunk 11 17 20 21

Category: Java Virtual Machine / Compiler

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
threadCount int Thread Count
tieredCompilation boolean Tiered Compilation
dynamicCompilerThreadCount boolean 20+ Uses Dynamic Number of Compiler Threads

Examples 3
startTime long: millis
494847531375
threadCount int
4
tieredCompilation boolean
true
startTime long: millis
531351860125
threadCount int
4
tieredCompilation boolean
true
startTime long: millis
471491652375
threadCount int
4
tieredCompilation boolean
true

JVM: Diagnostics

SyncOnValueBasedClass

experimental default profiling startTime eventThread stackTrace 16 17 20 21

Category: Java Virtual Machine / Diagnostics

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled stackTrace
default true true
profiling true true

Field Type Description
valueBasedClass Class Value Based Class Consider contributing a description to jfreventcollector.

HeapDump

default profiling startTime duration eventThread stackTrace 15 17 20 21

Category: Java Virtual Machine / Diagnostics

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled stackTrace threshold
default true true 0 ns
profiling true true 0 ns

Field Type Description
destination string Destination
size long Size
gcBeforeDump boolean GC Before Dump
onOutOfMemoryError boolean On Out of Memory Error

JVM: Flag

IntFlagChanged

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue int Old Value
newValue int New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

UnsignedIntFlagChanged

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue uint Old Value
newValue uint New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

LongFlagChanged

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue long Old Value
newValue long New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

UnsignedLongFlagChanged

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue ulong Old Value
newValue ulong New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

DoubleFlagChanged

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue double Old Value
newValue double New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

BooleanFlagChanged

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue boolean Old Value
newValue boolean New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

StringFlagChanged

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
name string Name
oldValue string Old Value
newValue string New Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

IntFlag

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value int Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
ActiveProcessorCount
origin FlagValueOrigin
Default
startTime long: millis
551742644167
value int
-1
name string
ParGCArrayScanChunk
origin FlagValueOrigin
Default
startTime long: millis
443590610833
value int
50
name string
ParGCArrayScanChunk
origin FlagValueOrigin
Default
startTime long: millis
547620541917
value int
50

UnsignedIntFlag

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value uint Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
ParallelGCThreads
origin FlagValueOrigin
Default
startTime long: millis
535482588417
value uint
8
name string
GCCardSizeInBytes
origin FlagValueOrigin
Default
startTime long: millis
448145320292
value uint
512
name string
G1ConcRefinementThreads
origin FlagValueOrigin
Ergonomic
startTime long: millis
487898220667
value uint
8

LongFlag

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value long Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
MaxTrivialSize
origin FlagValueOrigin
Default
startTime long: millis
381397833875
value long
6
name string
CIBreakAtOSR
origin FlagValueOrigin
Default
startTime long: millis
476739520750
value long
-1
name string
Tier3LoadFeedback
origin FlagValueOrigin
Default
startTime long: millis
483215039000
value long
5

UnsignedLongFlag

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value ulong Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
GCOverheadLimitThreshold
origin FlagValueOrigin
Default
startTime long: millis
483215056375
value ulong
5
name string
InitialRAMFraction
origin FlagValueOrigin
Default
startTime long: millis
476739536959
value ulong
64
name string
GCHeapFreeLimit
origin FlagValueOrigin
Default
startTime long: millis
381397953583
value ulong
2

DoubleFlag

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value double Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
SweeperThreshold
origin FlagValueOrigin
Default
startTime long: millis
400854269500
value double
0.5
name string
EscapeAnalysisTimeout
origin FlagValueOrigin
Default
startTime long: millis
494847581000
value double
20.0
name string
InitialRAMPercentage
origin FlagValueOrigin
Default
startTime long: millis
483215066625
value double
1.5625

BooleanFlag

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value boolean Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
StressCompiledExceptionHandlers
origin FlagValueOrigin
Default
startTime long: millis
476739570959
value boolean
false
name string
PrintIdeal
origin FlagValueOrigin
Default
startTime long: millis
381398045375
value boolean
false
name string
OptimizeIfOps
origin FlagValueOrigin
Default
startTime long: millis
483215069667
value boolean
true

StringFlag

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / Flag

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
name string Name
value string Value
origin FlagValueOrigin Origin Consider contributing a description to jfreventcollector.

Examples 3
name string
ArchiveClassesAtExit
origin FlagValueOrigin
Default
startTime long: millis
489885163667
value string
null
name string
HeapDumpPath
origin FlagValueOrigin
Default
startTime long: millis
400854377833
value string
null
name string
SharedArchiveFile
origin FlagValueOrigin
Default
startTime long: millis
482012749834
value string
null

JVM: GC: Collector

GarbageCollection

default profiling startTime duration 11 17 20 21

Category: Java Virtual Machine / GC / Collector

Garbage collection performed by the JVM

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
name GCName Name The name of the Garbage Collector
cause GCCause Cause The reason for triggering this Garbage Collection
sumOfPauses Tickspan Sum of Pauses Sum of all the times in which Java execution was paused during the garbage collection
longestPause Tickspan Longest Pause Longest individual pause during the garbage collection

Examples 3
cause GCCause
Allocation Failure
gcId uint
757
longestPause Tickspan
2693500
name GCName
DefNew
startTime long: millis
456903991333
sumOfPauses Tickspan
2693500
cause GCCause
G1 Humongous Allocation
gcId uint
787
longestPause Tickspan
6012792
name GCName
G1New
startTime long: millis
507392154250
sumOfPauses Tickspan
6012792
cause GCCause
Heap Inspection Initiated GC
gcId uint
493
longestPause Tickspan
7528792
name GCName
ParallelScavenge
startTime long: millis
547620889042
sumOfPauses Tickspan
7528792

SystemGC

default profiling startTime duration eventThread stackTrace 17 20 21

Category: Java Virtual Machine / GC / Collector

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled stackTrace threshold
default true true 0 ms
profiling true true 0 ms

Field Type Description
invokedConcurrent boolean Invoked Concurrent

Examples 3
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
481422656208
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
576791560834
invokedConcurrent boolean
false
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
()V
hidden boolean
false
modifiers int
257
name string
gc
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/lang/Runtime
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
567877024834

ParallelOldGarbageCollection

default profiling startTime duration 11 17 20 21

Category: Java Virtual Machine / GC / Collector

Appearing in: ParallelGC

Missing in: G1GC, SerialGC, ShenandoahGC, ZGC

Extra information specific to Parallel Old Garbage Collections

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
densePrefix ulong: address Dense Prefix The address of the dense prefix, used when compacting

Examples 1
densePrefix ulong: address
30257184768
gcId uint
568
startTime long: millis
596851758125

YoungGarbageCollection

default profiling startTime duration 11 17 20 21

Category: Java Virtual Machine / GC / Collector

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

Extra information specific to Young Garbage Collections

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
tenuringThreshold uint Tenuring Threshold

Examples 3
gcId uint
880
startTime long: millis
575114326459
tenuringThreshold uint
15
gcId uint
543
startTime long: millis
581150816625
tenuringThreshold uint
15
gcId uint
753
startTime long: millis
453985764958
tenuringThreshold uint
15

OldGarbageCollection

default profiling startTime duration 11 17 20 21

Category: Java Virtual Machine / GC / Collector

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

Extra information specific to Old Garbage Collections

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier

Examples 3
gcId uint
789
startTime long: millis
507468827709
gcId uint
764
startTime long: millis
465621552417
gcId uint
558
startTime long: millis
588923867375

G1GarbageCollection

default profiling startTime duration 11 17 20 21

Category: Java Virtual Machine / GC / Collector

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Extra information specific to G1 Young Garbage Collections

Configuration enabled threshold
default true 0 ms
profiling true 0 ms

Field Type Description
gcId uint GC Identifier
type G1YCType Type Consider contributing a description to jfreventcollector.

Examples 1
gcId uint
766
startTime long: millis
479282468042
type G1YCType
Concurrent Start

JVM: GC: Configuration

GCConfiguration

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / GC / Configuration

The configuration of the garbage collector

Configuration enabled period
default true everyChunk
profiling true everyChunk

Field Type Description
youngCollector GCName Young Garbage Collector The garbage collector used for the young generation
oldCollector GCName Old Garbage Collector The garbage collector used for the old generation
parallelGCThreads uint Parallel GC Threads Number of parallel threads to use for garbage collection
concurrentGCThreads uint Concurrent GC Threads Number of concurrent threads to use for garbage collection
usesDynamicGCThreads boolean Uses Dynamic GC Threads Whether a dynamic number of GC threads are used or not
isExplicitGCConcurrent boolean Concurrent Explicit GC Whether System.gc() is concurrent or not
isExplicitGCDisabled boolean Disabled Explicit GC Whether System.gc() will cause a garbage collection or not
pauseTarget long: millis Pause Target Target for GC pauses
gcTimeRatio uint GC Time Ratio Target for runtime vs garbage collection time

Examples 3
concurrentGCThreads uint
0
gcTimeRatio uint
99
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
SerialOld
parallelGCThreads uint
0
pauseTarget long: millis
-9223372036854775808
startTime long: millis
391018394917
usesDynamicGCThreads boolean
true
youngCollector GCName
DefNew
concurrentGCThreads uint
0
gcTimeRatio uint
99
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
ParallelOld
parallelGCThreads uint
8
pauseTarget long: millis
-9223372036854775808
startTime long: millis
542144220125
usesDynamicGCThreads boolean
true
youngCollector GCName
ParallelScavenge
concurrentGCThreads uint
2
gcTimeRatio uint
12
isExplicitGCConcurrent boolean
false
isExplicitGCDisabled boolean
false
oldCollector GCName
G1Old
parallelGCThreads uint
8
pauseTarget long: millis
-9223372036854775808
startTime long: millis
536487071459
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New

GCSurvivorConfiguration

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / GC / Configuration

The configuration of the survivors of garbage collection

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
maxTenuringThreshold ubyte Maximum Tenuring Threshold Upper limit for the age of how old objects to keep in the survivor area
initialTenuringThreshold ubyte Initial Tenuring Threshold Initial age limit for how old objects to keep in survivor area

Examples 3
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
429367066833
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
563210583667
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
552410512584

GCTLABConfiguration

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / GC / Configuration

The configuration of the Thread Local Allocation Buffers (TLABs)

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
usesTLABs boolean TLABs Used If Thread Local Allocation Buffers (TLABs) are in use
minTLABSize ulong: bytes Minimum TLAB Size
tlabRefillWasteLimit ulong: bytes TLAB Refill Waste Limit

Examples 3
minTLABSize ulong: bytes
2048
startTime long: millis
485363678917
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
535807275625
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
507758310750
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true

GCHeapConfiguration

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / GC / Configuration

The configuration of the garbage collected heap

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
minSize ulong: bytes Minimum Heap Size
maxSize ulong: bytes Maximum Heap Size
initialSize ulong: bytes Initial Heap Size
usesCompressedOops boolean If Compressed Oops Are Used If compressed Oops (Ordinary Object Pointers) are enabled
compressedOopsMode NarrowOopMode Compressed Oops Mode The kind of compressed oops being used
objectAlignment ulong: bytes Object Alignment Object alignment (in bytes) on the heap
heapAddressBits ubyte Heap Address Size Heap Address Size (in bits)

Examples 3
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
268435456
maxSize ulong: bytes
4294967296
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
585002403375
usesCompressedOops boolean
true
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
268435456
maxSize ulong: bytes
4294967296
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
572535217084
usesCompressedOops boolean
true
compressedOopsMode NarrowOopMode
Zero based
heapAddressBits ubyte
32
initialSize ulong: bytes
268435456
maxSize ulong: bytes
4294967296
minSize ulong: bytes
8388608
objectAlignment ulong: bytes
8
startTime long: millis
471830549625
usesCompressedOops boolean
true

YoungGenerationConfiguration

default profiling startTime duration end chunk 11 17 20 21

Category: Java Virtual Machine / GC / Configuration

The configuration of the young generation of the garbage collected heap

Configuration enabled period
default true beginChunk
profiling true beginChunk

Field Type Description
minSize ulong: bytes Minimum Young Generation Size
maxSize ulong: bytes Maximum Young Generation Size
newRatio uint New Ratio The size of the young generation relative to the tenured generation

Examples 3
maxSize ulong: bytes
2575302656
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
507758313084
maxSize ulong: bytes
1431633920
minSize ulong: bytes
89456640
newRatio uint
2
startTime long: millis
381844581875
maxSize ulong: bytes
1431306240
minSize ulong: bytes
89128960
newRatio uint
2
startTime long: millis
531606420542

JVM: GC: Detailed

ZThreadDebug

internal startTime duration eventThread 18 20 21

Category: Java Virtual Machine / GC / Detailed

Temporary latency measurements used during development and debugging of ZGC

Only valid for the ZGC.

Field Type Description
gcId uint GC Identifier
name string Name The name of the GC runner

G1MMU

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
timeSlice long: millis Time Slice Time slice used to calculate MMU
gcTime long: millis GC Time Time stopped because of GC during last time slice
pauseTarget long: millis Pause Target Max time allowed to be spent on GC during last time slice

Examples 1
gcId uint
869
gcTime long: millis
4
pauseTarget long: millis
200
startTime long: millis
569533806959
timeSlice long: millis
201

EvacuationInformation

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
cSetRegions uint Collection Set Regions
cSetUsedBefore ulong: bytes Collection Set Before Memory usage before GC in the collection set regions
cSetUsedAfter ulong: bytes Collection Set After Memory usage after GC in the collection set regions
allocationRegions uint Allocation Regions Regions chosen as allocation regions during evacuation (includes survivors and old space regions)
allocationRegionsUsedBefore ulong: bytes Allocation Regions Before Memory usage before GC in allocation regions
allocationRegionsUsedAfter ulong: bytes Allocation Regions After Memory usage after GC in allocation regions
bytesCopied ulong: bytes Bytes Copied
regionsFreed uint Regions Freed

Examples 1
allocationRegions uint
1
allocationRegionsUsedAfter ulong: bytes
947752
allocationRegionsUsedBefore ulong: bytes
0
bytesCopied ulong: bytes
947752
cSetRegions uint
6
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
11280264
gcId uint
763
regionsFreed uint
6
startTime long: millis
476719560000

ObjectCountAfterGC

startTime 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled
default false
profiling false

Field Type Description
gcId uint GC Identifier
objectClass Class Object Class Consider contributing a description to jfreventcollector.
count long Count
totalSize ulong: bytes Total Size

Examples 3
count long
93492
gcId uint
712
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/lang/Object
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
startTime long: millis
401221835958
totalSize ulong: bytes
1495872
count long
119
gcId uint
767
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
Ljava/internal/vm/FillerArray;
package Package
null
startTime long: millis
479650322625
totalSize ulong: bytes
4578056
count long
282830
gcId uint
466
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/lang/String
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
startTime long: millis
497859420542
totalSize ulong: bytes
6787920

G1EvacuationYoungStatistics

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Memory related evacuation statistics during GC for the young generation

Configuration enabled
default true
profiling true

Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 1
startTime long: millis
479288381875
statistics G1EvacuationStatistics
allocated ulong: bytes
1048520
directAllocated ulong: bytes
276416
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
766
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
977184
wasted ulong: bytes
2416

G1EvacuationOldStatistics

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Memory related evacuation statistics during GC for the old generation

Configuration enabled
default true
profiling true

Field Type Description
statistics G1EvacuationStatistics struct Evacuation Statistics

Examples 1
startTime long: millis
574746483334
statistics G1EvacuationStatistics
allocated ulong: bytes
0
directAllocated ulong: bytes
0
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
877
regionEndWaste ulong: bytes
0
regionsRefilled uint
0
undoWaste ulong: bytes
0
used ulong: bytes
0
wasted ulong: bytes
0

G1BasicIHOP

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Basic statistics related to current IHOP calculation

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
threshold ulong: bytes Current IHOP Threshold Current IHOP threshold
thresholdPercentage float: percentage Current IHOP Threshold Current IHOP threshold in percent of old generation
targetOccupancy ulong: bytes Target Occupancy Target old generation occupancy to reach at the start of mixed GC
currentOccupancy ulong: bytes Current Occupancy Current old generation occupancy
recentMutatorAllocationSize ulong: bytes Recent Mutator Allocation Size Mutator allocation during mutator operation in the most recent interval
recentMutatorDuration long: millis Recent Mutator Duration Time the mutator ran in the most recent interval
recentAllocationRate double: bytes-per-second Recent Allocation Rate Allocation rate of the mutator in the most recent interval in bytes/second
lastMarkingDuration long: millis Last Marking Duration Last time from the end of the last concurrent start to the first mixed GC

Examples 1
currentOccupancy ulong: bytes
167532200
gcId uint
821
lastMarkingDuration long: millis
468
recentAllocationRate double: bytes-per-second
0.0
recentMutatorAllocationSize ulong: bytes
0
recentMutatorDuration long: millis
594
startTime long: millis
540961584459
targetOccupancy ulong: bytes
1314914304
threshold ulong: bytes
0
thresholdPercentage float: percentage
0.0

G1AdaptiveIHOP

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Statistics related to current adaptive IHOP calculation

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
threshold ulong: bytes Threshold Current IHOP Threshold
thresholdPercentage float: percentage Threshold Current IHOP threshold in percent of the internal target occupancy
ihopTargetOccupancy ulong: bytes IHOP Target Occupancy Internal target old generation occupancy to reach at the start of mixed GC
currentOccupancy ulong: bytes Current Occupancy Current old generation occupancy
additionalBufferSize ulong: bytes Additional Buffer Additional buffer size
predictedAllocationRate double: bytes-per-second Predicted Allocation Rate Current predicted allocation rate for the mutator in bytes/second
predictedMarkingDuration long: millis Predicted Marking Duration Current predicted time from the end of the last concurrent start to the first mixed GC
predictionActive boolean Prediction Active Indicates whether the adaptive IHOP prediction is active

Examples 1
additionalBufferSize ulong: bytes
293601280
currentOccupancy ulong: bytes
654418760
gcId uint
859
ihopTargetOccupancy ulong: bytes
1051931443
predictedAllocationRate double: bytes-per-second
2.1331598578683525E8
predictedMarkingDuration long: millis
1520
predictionActive boolean
true
startTime long: millis
562246131250
threshold ulong: bytes
434025949
thresholdPercentage float: percentage
0.4125991

PromoteObjectInNewPLAB

profiling startTime eventThread 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC

Missing in: SerialGC, ShenandoahGC, ZGC

Object survived scavenge and was copied to a new Promotion Local Allocation Buffer (PLAB). Supported GCs are Parallel Scavenge, G1 and CMS with Parallel New. Due to promotion being done in parallel an object might be reported multiple times as the GC threads race to copy all objects.

Configuration enabled
default false
profiling true

Field Type Description
gcId uint GC Identifier Identifier signifying GC during which the object was promoted
objectClass Class Object Class Class of promoted object
objectSize ulong: bytes Object Size Size of promoted object
tenuringAge uint Object Tenuring Age Tenuring age of a surviving object before being copied. The tenuring age of an object is a value between 0-15 and is incremented each scavenge the object survives. Newly allocated objects have tenuring age 0.
tenured boolean Tenured True if object was promoted to Old space, otherwise the object was aged and copied to a Survivor space
plabSize ulong: bytes PLAB Size Size of the allocated PLAB to which the object was copied

Examples 2
gcId uint
457
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[F
package Package
null
objectSize ulong: bytes
56
plabSize ulong: bytes
32752
startTime long: millis
483216125417
tenured boolean
false
tenuringAge uint
0
gcId uint
763
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[F
package Package
null
objectSize ulong: bytes
56
plabSize ulong: bytes
21904
startTime long: millis
476717808209
tenured boolean
false
tenuringAge uint
0

PromoteObjectOutsidePLAB

profiling startTime eventThread 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC

Missing in: SerialGC, ShenandoahGC, ZGC

Object survived scavenge and was copied directly to the heap. Supported GCs are Parallel Scavenge, G1 and CMS with Parallel New. Due to promotion being done in parallel an object might be reported multiple times as the GC threads race to copy all objects.

Configuration enabled
default false
profiling true

Field Type Description
gcId uint GC Identifier Identifier signifying GC during which the object was promoted
objectClass Class Object Class Class of promoted object
objectSize ulong: bytes Object Size Size of promoted object
tenuringAge uint Object Tenuring Age Tenuring age of a surviving object before being copied. The tenuring age of an object is a value between 0-15 and is incremented each scavenge the object survives. Newly allocated objects have tenuring age 0.
tenured boolean Tenured True if object was promoted to Old space, otherwise the object was aged and copied to a Survivor space

Examples 2
gcId uint
790
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
0
name string
[Ljava/io/ObjectInputStream$HandleTable$HandleList;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/io
objectSize ulong: bytes
11280
startTime long: millis
509483308917
tenured boolean
false
tenuringAge uint
0
gcId uint
463
objectClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
0
name string
[Lorg/apache/spark/unsafe/memory/MemoryBlock;
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/unsafe/memory
objectSize ulong: bytes
32784
startTime long: millis
492606258167
tenured boolean
false
tenuringAge uint
0

PromotionFailed

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Promotion of an object failed

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
promotionFailed CopyFailed struct Promotion Failed Data
thread Thread Running thread

EvacuationFailed

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Evacuation of an object failed

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
evacuationFailed CopyFailed struct Evacuation Failed Data

ConcurrentModeFailure

default profiling startTime 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC

Missing in: ParallelGC, SerialGC, ShenandoahGC, ZGC

Concurrent Mode failed

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier

Examples 1
gcId uint
764
startTime long: millis
476879007250

GCCPUTime

default profiling startTime 20 21

Category: Java Virtual Machine / GC / Detailed

GC CPU Time information. Supported: G1GC, ParallelGC and SerialGC

Configuration enabled
default true
profiling true

Field Type Description
gcId uint GC Identifier
userTime ulong: nanos User Time
systemTime ulong: nanos System Time
realTime ulong: nanos Real Time

AllocationRequiringGC

startTime eventThread stackTrace 11 17 20 21

Category: Java Virtual Machine / GC / Detailed

Appearing in: G1GC, ParallelGC, SerialGC

Missing in: ShenandoahGC, ZGC

No additional description available. Write your own and contribute it to jfreventcollector or directly to the OpenJDK.

Configuration enabled stackTrace
default false true
profiling false true

Field Type Description
gcId uint Pending GC Identifier
size ulong: bytes Allocation Size

Examples 3
gcId uint
911
size ulong: bytes
2048
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
120
method Method
descriptor string
(Lcom/twitter/util/Try;)Lcom/twitter/util/Future;
hidden boolean
false
modifiers int
1
name string
const
type Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
49
name string
com/twitter/util/Future$
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
com/twitter/util
type FrameType
Inlined
truncated boolean
false
startTime long: millis
612479405125
gcId uint
746
size ulong: bytes
24
stackTrace StackTrace
frames <