Introduction

The following are the events for the OpenJDK 21 (jdk-21+15, 26-March-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
536626408042
total ulong: bytes
588938
amount ulong: bytes
660
startTime long: millis
498194392834
total ulong: bytes
660
amount ulong: bytes
16356
startTime long: millis
439990282750
total ulong: bytes
1374244

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
246
flushId ulong
350
size ulong: bytes
50227
startTime long: millis
604282522167
elements ulong
3598
flushId ulong
172
size ulong: bytes
1103588
startTime long: millis
483336611084
elements ulong
5752
flushId ulong
214
size ulong: bytes
959357
startTime long: millis
487372360333

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_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
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_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

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
45
name string
enabled
stackTrace StackTrace
null
startTime long: millis
381379409250
value string
true
id long
1479
name string
threshold
stackTrace StackTrace
null
startTime long: millis
483203615292
value string
10 ms
id long
89
name string
enabled
stackTrace StackTrace
null
startTime long: millis
476715963750
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_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
443575897167
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
508761828500
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
619359387250

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.specification.name
startTime long: millis
429022745708
value string
Java Virtual Machine Specification
key string
java.vm.compressedOopsMode
startTime long: millis
508761861500
value string
Zero based
key string
java.home
startTime long: millis
487872224542
value string
[...]/.sdkman/candidates/java/19-sapmchn

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$18856+0x0000000804247080/1741599207
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
org/apache/spark/storage
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
0
lineNumber int
-1
method Method
descriptor string
(Ljava/lang/ClassLoader;Ljava/lang/Class;Ljava/lang/String;[BIILjava/security/ProtectionDomain;ZILjava/lang/Object;)Ljava/lang/Class;
hidden boolean
false
modifiers int
264
name string
defineClass0
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
1057
name string
java/lang/ClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/lang
type FrameType
Native
truncated boolean
false
startTime long: millis
445005730375
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
48
name string
java.lang.invoke.LambdaForm$MH+0x0000000800242000/1634717656
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
484513587125
definingClassLoader ClassLoader
null
initiatingClassLoader ClassLoader
null
loadedClass Class
classLoader ClassLoader
null
hidden boolean
true
modifiers int
48
name string
java.lang.invoke.LambdaForm$MH+0x00000008041f8400/2056910531
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
502792795959

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/sql/Encoders$$typecreator1$11
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/sql
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
537859501459
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/sql/Encoders$$typecreator1$2
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/sql
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
450107186833
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/sql/SQLImplicits$$typecreator1$7
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/sql
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
553761918959

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
543927320917
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
49
name string
scala/reflect/ManifestFactory$BooleanManifest
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
location string
null
name string
null
version string
null
name string
scala/reflect
definingClassLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
startTime long: millis
559700777667
unloadedClass Class
classLoader ClassLoader
name string
null
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/net/URLClassLoader
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/net
hidden boolean
false
modifiers int
49
name string
scala/reflect/ManifestFactory$AnyManifest
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
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
458806026667
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
49
name string
scala/concurrent/stm/ccstm/InTxnImpl$
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/concurrent/stm/ccstm

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 'profiled nmethods'
entryCount int
25390
fullCount int
0
methodCount int
25390
reservedTopAddress ulong: address
5223170048
startAddress ulong: address
5100273664
startTime long: millis
470835542500
unallocatedCapacity ulong: bytes
48915072
adaptorCount int
0
codeBlobType CodeBlobType
CodeHeap 'non-profiled nmethods'
entryCount int
20281
fullCount int
0
methodCount int
20281
reservedTopAddress ulong: address
5754585088
startAddress ulong: address
5631672320
startTime long: millis
558813426084
unallocatedCapacity ulong: bytes
83355136
adaptorCount int
1858
codeBlobType CodeBlobType
CodeHeap 'non-nmethods'
entryCount int
1946
fullCount int
0
methodCount int
0
reservedTopAddress ulong: address
5238521856
startAddress ulong: address
5232672768
startTime long: millis
531351862542
unallocatedCapacity ulong: bytes
3411712

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
381397790333
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
507460806000
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
585978467000

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 int 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
16400
compileId int
59252
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
696
isOsr boolean
false
method 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
startTime long: millis
476403056250
succeded boolean
true
codeSize ulong: bytes
2584
compileId int
60862
compileLevel ushort
3
compiler CompilerType
c1
inlinedBytes ulong: bytes
44
isOsr boolean
false
method Method
descriptor string
(Ljava/util/Queue;)Z
hidden boolean
false
modifiers int
20
name string
runAllTasksFrom
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
1057
name string
io/netty/util/concurrent/SingleThreadEventExecutor
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
io/netty/util/concurrent
startTime long: millis
450817346958
succeded boolean
true
codeSize ulong: bytes
61784
compileId int
70436
compileLevel ushort
2
compiler CompilerType
c1
inlinedBytes ulong: bytes
2026
isOsr boolean
false
method Method
descriptor string
(Lorg/apache/xbean/asm9/MethodVisitor;Lorg/apache/xbean/asm9/Context;I)V
hidden boolean
false
modifiers int
2
name string
readCode
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/xbean/asm9/ClassReader
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/xbean/asm9
startTime long: millis
576789166459
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 int 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 int Compilation Identifier

Examples 3
compileId int
70552
failureMessage string
concurrent class loading
startTime long: millis
567868026750
compileId int
70411
failureMessage string
concurrent class loading
startTime long: millis
576786520292
compileId int
70375
failureMessage string
concurrent class loading
startTime long: millis
473461510833

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 int 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
13
callee CalleeMethod
descriptor string
()Z
name string
cancellationRequested
type string
java/util/stream/Sink
caller Method
descriptor string
()Z
hidden boolean
false
modifiers int
1
name string
cancellationRequested
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/util/stream/SliceOps$2$1
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 int
58956
message string
inline (hot)
startTime long: millis
483204344250
succeeded boolean
true
bci int
2
callee CalleeMethod
descriptor string
(Ljava/lang/Object;)Lscala/Option;
name string
get
type string
scala/collection/MapOps
caller Method
descriptor string
(Ljava/lang/Object;)Z
hidden boolean
false
modifiers int
1
name string
contains
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/MapOps
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
compileId int
59185
message string
no static binding
startTime long: millis
381397746792
succeeded boolean
false
bci int
1
callee CalleeMethod
descriptor string
()J
name string
finishTime
type string
org/apache/spark/scheduler/TaskInfo
caller Method
descriptor string
()Z
hidden boolean
false
modifiers int
1
name string
finished
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/TaskInfo
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
compileId int
59252
message string
inline
startTime long: millis
476403129084
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 int 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
reinterpret
bci int
37
compileId int
29506
compiler CompilerType
c2
instruction Bytecode
ifnonnull
lineNumber int
1669
method Method
descriptor string
()I
hidden boolean
false
modifiers int
16
name string
getFence
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/util/HashMap$HashMapSpliterator
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/util
reason DeoptimizationReason
unstable_if
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
37
lineNumber int
1669
method Method
descriptor string
()I
hidden boolean
false
modifiers int
16
name string
getFence
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/util/HashMap$HashMapSpliterator
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
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
450718873042
action DeoptimizationAction
reinterpret
bci int
37
compileId int
20277
compiler CompilerType
c2
instruction Bytecode
ifnonnull
lineNumber int
1669
method Method
descriptor string
()I
hidden boolean
false
modifiers int
16
name string
getFence
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/util/HashMap$HashMapSpliterator
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.base
version string
19
name string
java/util
reason DeoptimizationReason
unstable_if
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
37
lineNumber int
1669
method Method
descriptor string
()I
hidden boolean
false
modifiers int
16
name string
getFence
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
32
name string
java/util/HashMap$HashMapSpliterator
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
type FrameType
JIT compiled
truncated boolean
false
startTime long: millis
538300614500
action DeoptimizationAction
reinterpret
bci int
5
compileId int
24613
compiler CompilerType
c2
instruction Bytecode
ifge
lineNumber int
1026
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
17
name string
acquireShared
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
5
lineNumber int
1026
method Method
descriptor string
(I)V
hidden boolean
false
modifiers int
17
name string
acquireShared
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
560454086750

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
64582
invalidatedCount int
0
nmethodCodeSize ulong: bytes
79755264
nmethodsSize ulong: bytes
127497176
osrBytesCompiled ulong: bytes
0
osrCompileCount int
680
peakTimeSpent long: millis
20643
standardBytesCompiled ulong: bytes
0
standardCompileCount int
63902
startTime long: millis
575561205667
totalTimeSpent long: millis
755336
bailoutCount int
12
compileCount int
79416
invalidatedCount int
0
nmethodCodeSize ulong: bytes
110317952
nmethodsSize ulong: bytes
173415280
osrBytesCompiled ulong: bytes
0
osrCompileCount int
733
peakTimeSpent long: millis
19331
standardBytesCompiled ulong: bytes
0
standardCompileCount int
78683
startTime long: millis
590150830584
totalTimeSpent long: millis
479956
bailoutCount int
14
compileCount int
79619
invalidatedCount int
0
nmethodCodeSize ulong: bytes
104523904
nmethodsSize ulong: bytes
168976184
osrBytesCompiled ulong: bytes
0
osrCompileCount int
759
peakTimeSpent long: millis
9368
standardBytesCompiled ulong: bytes
0
standardCompileCount int
78860
startTime long: millis
493877378917
totalTimeSpent long: millis
540921

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
476739505625
threadCount int
4
tieredCompilation boolean
true
startTime long: millis
448145311625
threadCount int
4
tieredCompilation boolean
true
startTime long: millis
483215015417
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

Information about a successfully written Java heap dump

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

Field Type Description
destination string Destination Path of the Dump
size long Size
gcBeforeDump boolean GC Before Dump
onOutOfMemoryError boolean Heap Dump on Out of Memory Error
overwrite boolean 21+ Overwrite Heap dump overwrites previous file location if it exists
compression int 21+ Compression Level Compression level of the dump, if larger than 0 we use gzip compression with this level

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
VerifyMetaspaceInterval
origin FlagValueOrigin
Default
startTime long: millis
588922524000
value int
0
name string
DeoptimizeObjectsALotThreadCountSingle
origin FlagValueOrigin
Default
startTime long: millis
476739510792
value int
1
name string
VerifyMetaspaceInterval
origin FlagValueOrigin
Default
startTime long: millis
431570198708
value int
0

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
StringDeduplicationAgeThreshold
origin FlagValueOrigin
Default
startTime long: millis
487898220167
value uint
3
name string
G1RemSetArrayOfCardsEntriesBase
origin FlagValueOrigin
Default
startTime long: millis
438636160542
value uint
4
name string
StringDeduplicationAgeThreshold
origin FlagValueOrigin
Default
startTime long: millis
552281875334
value uint
3

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
483215036750
value long
6
name string
MaxLoopPad
origin FlagValueOrigin
Default
startTime long: millis
476739516417
value long
15
name string
Tier2BackEdgeThreshold
origin FlagValueOrigin
Default
startTime long: millis
381397836833
value long
0

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
MaxVirtMemFraction
origin FlagValueOrigin
Default
startTime long: millis
476739537084
value ulong
2
name string
NUMASpaceResizeRate
origin FlagValueOrigin
Default
startTime long: millis
483215060125
value ulong
1073741824
name string
TLABWasteIncrement
origin FlagValueOrigin
Default
startTime long: millis
381398002792
value ulong
4

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
InitialRAMPercentage
origin FlagValueOrigin
Default
startTime long: millis
416003485500
value double
1.5625
name string
ZFragmentationLimit
origin FlagValueOrigin
Default
startTime long: millis
489885068084
value double
25.0
name string
ZFragmentationLimit
origin FlagValueOrigin
Default
startTime long: millis
507460857959
value double
25.0

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
NeverActAsServerClassMachine
origin FlagValueOrigin
Default
startTime long: millis
483215105167
value boolean
false
name string
UseCompressedOops
origin FlagValueOrigin
Ergonomic
startTime long: millis
381398021375
value boolean
true
name string
ClassUnloading
origin FlagValueOrigin
Default
startTime long: millis
476739571917
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
StartFlightRecording
origin FlagValueOrigin
Command line
startTime long: millis
381398121583
value string
filename=[...]/code/experiments/jfreventcollector/jfr/sample_UseSerialGC.jfr,settings=[...]/code/experiments/jfreventcollector/.cache/jfc.jfc
name string
HeapDumpPath
origin FlagValueOrigin
Default
startTime long: millis
489885161000
value string
null
name string
OnOutOfMemoryError
origin FlagValueOrigin
Default
startTime long: millis
487898302459
value string

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
Heap Inspection Initiated GC
gcId uint
762
longestPause Tickspan
418481833
name GCName
SerialOld
startTime long: millis
458697831625
sumOfPauses Tickspan
418481833
cause GCCause
Heap Inspection Initiated GC
gcId uint
797
longestPause Tickspan
272291542
name GCName
G1Full
startTime long: millis
524785456000
sumOfPauses Tickspan
272291542
cause GCCause
Heap Inspection Initiated GC
gcId uint
534
longestPause Tickspan
175663708
name GCName
ParallelOld
startTime long: millis
575188826334
sumOfPauses Tickspan
175663708

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
554602703375
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
455492918583
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
591579970834

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
30065295360
gcId uint
564
startTime long: millis
595020895167

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
850
startTime long: millis
556219961375
tenuringThreshold uint
15
gcId uint
744
startTime long: millis
452888334375
tenuringThreshold uint
15
gcId uint
479
startTime long: millis
532346110125
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
498
startTime long: millis
552284174750
gcId uint
788
startTime long: millis
473466134458
gcId uint
786
startTime long: millis
505643414709

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
763
startTime long: millis
476716162709
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
ParallelOld
parallelGCThreads uint
8
pauseTarget long: millis
-9223372036854775808
startTime long: millis
549472041209
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
593476997834
usesDynamicGCThreads boolean
true
youngCollector GCName
G1New
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
459121629667
usesDynamicGCThreads boolean
true
youngCollector GCName
DefNew

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
522032611792
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
563210583667
initialTenuringThreshold ubyte
7
maxTenuringThreshold ubyte
15
startTime long: millis
431885220917

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
542144224250
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
429367067875
tlabRefillWasteLimit ulong: bytes
64
usesTLABs boolean
true
minTLABSize ulong: bytes
2048
startTime long: millis
563210584584
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
531606419167
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
482414441959
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
439103795125
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
1431633920
minSize ulong: bytes
89456640
newRatio uint
2
startTime long: millis
443917122667
maxSize ulong: bytes
1431306240
minSize ulong: bytes
89128960
newRatio uint
2
startTime long: millis
490099315542
maxSize ulong: bytes
2575302656
minSize ulong: bytes
1363144
newRatio uint
2
startTime long: millis
495019018584

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
808
gcTime long: millis
74
pauseTarget long: millis
200
startTime long: millis
538971487584
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
3
allocationRegionsUsedAfter ulong: bytes
4176400
allocationRegionsUsedBefore ulong: bytes
947712
bytesCopied ulong: bytes
3228688
cSetRegions uint
402
cSetUsedAfter ulong: bytes
0
cSetUsedBefore ulong: bytes
842120568
gcId uint
852
regionsFreed uint
402
startTime long: millis
556676865417

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
75364
gcId uint
468
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/lang/Class
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
503217812084
totalSize ulong: bytes
8771672
count long
48371
gcId uint
765
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
48
name string
java/lang/invoke/MemberName
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
startTime long: millis
476816729417
totalSize ulong: bytes
2321808
count long
57169
gcId uint
713
objectClass Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
49
name string
java/lang/reflect/Method
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/reflect
startTime long: millis
406435462625
totalSize ulong: bytes
5030872

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
497151436084
statistics G1EvacuationStatistics
allocated ulong: bytes
2036360
directAllocated ulong: bytes
159288
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
780
regionEndWaste ulong: bytes
0
regionsRefilled uint
2
undoWaste ulong: bytes
0
used ulong: bytes
1909552
wasted ulong: bytes
3968

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
574766049792
statistics G1EvacuationStatistics
allocated ulong: bytes
20640
directAllocated ulong: bytes
272
failureUsed ulong: bytes
0
failureWaste ulong: bytes
0
gcId uint
878
regionEndWaste ulong: bytes
0
regionsRefilled uint
1
undoWaste ulong: bytes
0
used ulong: bytes
15072
wasted ulong: bytes
264

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
141797008
gcId uint
835
lastMarkingDuration long: millis
266
recentAllocationRate double: bytes-per-second
24259.183898413823
recentMutatorAllocationSize ulong: bytes
6192
recentMutatorDuration long: millis
255
startTime long: millis
545411446417
targetOccupancy ulong: bytes
497025024
threshold ulong: bytes
79174622
thresholdPercentage float: percentage
0.15929705

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
1231028224
currentOccupancy ulong: bytes
209854320
gcId uint
790
ihopTargetOccupancy ulong: bytes
1950456217
predictedAllocationRate double: bytes-per-second
4.728535042093943E8
predictedMarkingDuration long: millis
1757
predictionActive boolean
true
startTime long: millis
509487367917
threshold ulong: bytes
0
thresholdPercentage float: percentage
0.0

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
483216593417
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
476717633417
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
459
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
485541229584
tenured boolean
false
tenuringAge uint
0
gcId uint
776
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
490275106459
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
760
size ulong: bytes
112
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
7
lineNumber int
394
method Method
descriptor string
(Lscala/concurrent/stm/TxnExecutor;Lscala/Function1;)Ljava/lang/Object;
hidden boolean
false
modifiers int
2
name string
topLevelAtomicImpl
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
scala/concurrent/stm/ccstm/InTxnImpl
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/concurrent/stm/ccstm
type FrameType
Inlined
truncated boolean
false
startTime long: millis
457664029792
gcId uint
524
size ulong: bytes
56
stackTrace StackTrace
frames StackFrame
bytecodeIndex int
52
lineNumber int
239
method Method
descriptor string
(I)[Ljava/lang/Object;
hidden boolean
false
modifiers int
2
name string
grow
type Class
classLoader ClassLoader
name string
bootstrap
type Class
null
hidden boolean
false
modifiers int
33
name string
java/util/ArrayList
package Package
exported boolean
true
module Module
classLoader ClassLoader
name string
bootstrap
type Class
null
location string
jrt:/java.base
name string
java.b