7.6.1 -XX:[+|-]HitachiCommaVerboseGC

Description

-XX:[+|-]HitachiCommaVerboseGC specifies whether to output the extended verbosegc information in CSV format.

Prerequisite option

• -XX:+HitachiVerboseGC

Output format (for SerialGC)

Output format when the -XX:-HitachiVerboseGCIntervalTime option is specified:

id,date,full_count,copy_count,gc_kind,gc_info,gc_time,eden_info,
survivor_info,tenured_info,metaspace_info,classspace_info,cause_info,
user_cpu,system_cpu,jvm_alloc_size,mmap_total_size,malloc_total_size,
thread_count,doe_alloc_size,called_count,cc_used_size,cc_max_size,cc_info

The following provides details about the output.

Output item	Output content
id	Java VM log file identifier.
date	Start date and time of GC. This information is not output if the -XX:-HitachiVerboseGCPrintDate option is specified.
full_count	Number of times output of the Full GC information is skipped. This information is output if the -XX:HitachiVerboseGCIntervalTime option is specified.
copy_count	The number of times output of the CopyGC information is skipped. This information is output if the -XX:HitachiVerboseGCIntervalTime option is specified.
gc_kind	GC type. FullGC or GC is output.
gc_info	GC information. This information is output in the following format, where values are given in units of kilobytes: area_length_before_GC,area_length_after_GC,area_size
gc_time	Elapsed GC time. This information is output in units of seconds.
eden_info	Eden information. This information is output in the following format, where values are given in units of kilobytes: area_length_before_GC,area_length_after_GC,area_size
survivor_info	Survivor information. This information is output in the following format, where values are given in units of kilobytes: area_length_before_GC,area_length_after_GC,area_size
tenured_info	Tenured information. This information is output in the following format, where values are given in units of kilobytes: area_length_before_GC,area_length_after_GC,area_size
metaspace_info	Metaspace information. This information is output in the following format, where values are given in units of kilobytes: size_of_used_Metaspace_area_before_GC,capacity_of_Metaspace_area_before_GC,size_of_committed_Metaspace_area_before_GC,size_of_used_Metaspace_area_after_GC,capacity_of_Metaspace_area_after_GC,size_of_committed_Metaspace_area_after_GC
classspace_info	Compressed Class Space information. This information is output in the following format, where values are given in units of kilobytes: size_of_used_Compressed_Class_Space_before_GC,capacity_of_Compressed_Class_Space_before_GC,size_of_committed_Compressed_Class_Space_before_GC,size_of_used_Compressed_Class_Space_after_GC,capacity_of_Compressed_Class_Space_after_GC,size_of_committed_Compressed_Class_Space_after_GC If the functionality for the compressed object pointer is not used, 0 is output for each size.
cause_info	GC factor number. This information is not output if the -XX:-HitachiVerboseGCPrintCause option is specified.
user_cpu	Amount of CPU time that the GC thread spent in user mode. This information is output in units of seconds. If acquisition of the CPU time fails, unknown is displayed. This information is not output if the -XX:-HitachiVerboseGCCpuTime option is specified.
system_cpu	Amount of CPU time that the GC thread spent in kernel mode. This information is output in units of seconds. If acquisition of the CPU time fails, unknown is displayed. This information is not output if the -XX:-HitachiVerboseGCCpuTime option is specified.
jvm_alloc_size	Of the areas managed in Java VM, the size of the area that is currently in use (of the total size of mmap_total_size and malloc_total_size, the size of the area that is currently in use). This information is output in units of kilobytes. This information is not output if the -XX:-HitachiVerboseGCPrintJVMInternalMemory option is specified.
mmap_total_size	Of the areas managed in Java VM, the total size of the C heap assigned by mmap. This information is output in units of kilobytes. This information is not output if the -XX:-HitachiVerboseGCPrintJVMInternalMemory option is specified.
malloc_total_size	Of the areas managed in Java VM, the total size of the C heap assigned by malloc. This information is output in units of kilobytes. This information is not output if the -XX:-HitachiVerboseGCPrintJVMInternalMemory option is specified.
thread_count	Number of Java threads. This information is not output if the -XX:-HitachiVerboseGCPrintThreadCount option is specified.
doe_alloc_size	Accumulated size of the heap that was secured by calling java.io.File.deleteOnExit(). This information is output in units of kilobytes. This information is not output if the -XX:-HitachiVerboseGCPrintDeleteOnExit option is specified.
called_count	Number of times java.io.File.deleteOnExit() was called. This information is not output if the -XX:-HitachiVerboseGCPrintDeleteOnExit option is specified.
cc_used_size	Size of the used code cache area when GC occurred. This information is output in units of kilobytes. This information is not output if the -XX:-PrintCodeCacheInfo option is specified.
cc_max_size	Maximum size of the code cache area. This information is output in units of kilobytes. This information is not output if the -XX:-PrintCodeCacheInfo option is specified.
cc_info	Maintenance information. This information is not output if the -XX:-PrintCodeCacheInfo option is specified.

Output format when the -XX:+HitachiVerboseGCPrintTenuringDistribution option is specified:

id, date, size, value, max_value, total_age1, total_age2, total_age_n

The following provides details about the output.

Output item	Output content
id	PTD (JavaVM log file identifier).
date	Date and time the GC started.
size	Target size of the objects in the Survivor area after GC.
value	Tenure threshold value for the Java objects that will be promoted to the Tenured area in the next CopyGC. This value is dynamically set for each CopyGC, based on the values specified in the -XX:MaxTenuringThreshold=value option, the memory size of the Survivor area, and the -XX:TargetSurvivorRatio=value option. The Java objects for which the tenure value is value or more will be promoted to the Tenured area in the next CopyGC.
max_value	Maximum value (the value specified in the MaxTenuringThreshold option) of the tenure threshold value (value) for the Java objects that will be promoted to the Tenured area in the CopyGC. value is dynamically set for each CopyGC, but does not exceed max_value. The Java objects for which the tenure value is max_value or more always will be promoted to the Tenured area in the next CopyGC.
total_age1	Total number of bytes of 1-year-old objects.
total_age2	Total number of bytes of 1-to-2-year-old objects.
total_agen	Total number of bytes of 1-to-n-year-old objects. If n is close to max_value, it means that an object with a long life exists.

Output format (for G1GC)

Log entries related to GC and log entries related to concurrent marking are output to the Java VM log file. The log entry for one concurrent marking is divided into two or more lines for output, because concurrent marking executes processing in parallel with other applications.

Output format of the log entries related to GC

id,date,gc_kind,gc_info,gc_time,gc_status,eden_info,survivor_info,tenured_info,
humongous_info,free_info,metaspace_info,classspace_info,cause_info,
region_size,target_time,predicted_time,target_size,reclaimable_info,user_cpu,
system_cpu,jvm_alloc_size,mmap_total_size,malloc_total_size,thread_count,
doe_alloc_size,called_count,cc_used_size,cc_max_size,cc_info

Output format of the log entries related to concurrent marking

id,date,cm_event,user_cpu,sys_spu

The following provides details about the output.

Classification	Output item	Output content
Log entry related to GC	id	VG1 (Java VM log file identifier)
	date	Start date and time of GC. This information is not output if the -XX:-HitachiVerboseGCPrintDate option is specified.
	gc_kind	Type of GC or Concurrent Marking. One of the following is output: FullGC, Mixed GC, Young GC, Young GC(initial-mark), CM Remark, or CM Cleanup.
	gc_info	Memory information of the JavaHeap area. This information is output in the following format, where values are given in units of kilobytes: size_of_used_JavaHeap_area_before_GC,size_of_used_JavaHeap_area_before_GC#,size_of_used_JavaHeap_area_before_GC#,size_of_used_JavaHeap_area_after_GC,size_of_used_JavaHeap_area_after_GC#,size_of_used_JavaHeap_area_after_GC#
	gc_time	Amount of time for which the application stopped due to GC. This information is output in units of seconds.
	gc_status	GC status. When a To space overflow occurs, to exhausted is output. In cases other than the above, - is output. For each type of GC, the GC status is output as follows. When gc_kind is Young GC, Young GC(initial-mark), or Mixed GC: - or to exhausted is output. When gc_kind is a type other than the above: - is output.
	eden_info	Memory information of the Eden area. This information is output in the following format, where values are given in units of kilobytes: size_of_used_Eden_area_before_GC#,maximum_size_that_can_be_acquired_by_Eden_area_before_GC#,size_of_used_Eden_area_after_GC#,maximum_size_that_can_be_acquired_by_Eden_area_after_GC# "maximum_size_that_can_be_acquired_by_Eden_area_before_GC" refers to "size_of_New_area - size_of_Survivor_area".
	survivor_info	Memory information of the Survivor area. This information is output in the following format, where values are given in units of kilobytes: size_of_used_Survivor_area_before_GC#,size_of_used_Survivor_area_after_GC#
	tenured_info	Memory information of the Tenured area. This information is output in the following format, where values are given in units of kilobytes: size_of_used_Tenured_area_before_GC#,size_of_used_Tenured_area_after_GC#
	humongous_info	Memory information of the Humongous area. This information is output in the following format, where values are given in units of kilobytes: size_of_used_Humongous_area_before_GC#,size_of_used_Humongous_area_after_GC#
	free_info	Memory information of the Free area. This information is output in the following format, where values are given in units of kilobytes: size_of_used_Free_area_before_GC#,size_of_used_Free_area_after_GC#
	metaspace_info	Metaspace information. This information is output in the following format, where values are given in units of kilobytes: size_of_used_Metaspace_area_before_GC,capacity_of_Metaspace_area_before_GC,size_of_committed_Metaspace_area_before_GC,size_of_used_Metaspace_area_after_GC,capacity_of_Metaspace_area_after_GC,size_of_committed_Metaspace_area_after_GC
	classspace_info	Compressed Class Space information. This information is output in the following format, where values are given in units of kilobytes: size_of_used_Compressed_Class_Space_before_GC,capacity_of_Compressed_Class_Space_before_GC,size_of_committed_Compressed_Class_Space_before_GC,size_of_used_Compressed_Class_Space_after_GC,capacity_of_Compressed_Class_Space_after_GC,size_of_committed_Compressed_Class_Space_after_GC If the functionality for the compressed object pointer is not used, 0 is output for each size.
	cause_info	GC factor number. This information is not output if the -XX:-HitachiVerboseGCPrintCause option is specified.
	region_size	Size of a single region. This information is output in units of kilobytes.
	target_time	Target amount of time for which applications are stopped due to GC. This information is output in units of seconds. You can specify the target time by using the -XX:+ MaxGCPauseMillis option.
	predicted_time	Amount of time for which applications will be stopped due to GC, as predicted by Java VM. This information is output in units of seconds. If the GC type is Full GC, CM Remark, or CM Cleanup, Java VM does not predict the stop time, and 0 is output.
	target_size	Size of the Tenured area that is subject to Mixed GC. This information is output in units of kilobytes. If the GC type is not Mixed GC, 0 is output.
	reclaimable_info	Information about the predicted collection size. This information is output in the following format: predicted_collection_size,predicted_collection_rate The predicted collection size is output in units of kilobytes. The predicted collection rate is output as a value with two decimal places. Note that the information about the predicted collection size is output only for Young GC or Mixed GC immediately after Concurrent Marking. In other cases, Java VM does not predict the collection size, and 0 is output.
	user_cpu	Total CPU time that all GC threads spent in user mode. This information is output in units of seconds. If acquisition of the CPU time fails, unknown is displayed, as in "[User: unknown]". This information is not output if the -XX:-HitachiVerboseGCCpuTime option is specified.
	system_cpu	Total CPU time that all GC threads spent in kernel mode. This information is output in units of seconds. If acquisition of the CPU time fails, unknown is displayed, as in "[Sys: unknown]". This information is not output if the -XX:-HitachiVerboseGCCpuTime option is specified.
	jvm_alloc_size	Of the areas managed in Java VM, the size of the area that is currently in use (of the total size of mmap_total_size and malloc_total_size, the size of the area that is currently in use). This information is not output if the -XX:-HitachiVerboseGCPrintJVMInternalMemory option is specified.
	mmap_total_size	Of the areas managed in Java VM, the total size of the C heap assigned by mmap. This information is not output if the -XX:-HitachiVerboseGCPrintJVMInternalMemory option is specified.
	malloc_total_size	Of the areas managed in Java VM, the total size of the C heap assigned by malloc. This information is not output if the -XX:-HitachiVerboseGCPrintJVMInternalMemory option is specified.
	thread_count	Number of Java threads. This information is not output if the -XX:-HitachiVerboseGCPrintThreadCount option is specified.
	doe_alloc_size	Accumulated size of the heap that was secured by calling java.io.File.deleteOnExit(). This information is not output if the -XX:-HitachiVerboseGCPrintDeleteOnExit option is specified.
	called_count	Number of times java.io.File.deleteOnExit() was called. This information is not output if the -XX:-HitachiVerboseGCPrintDeleteOnExit option is specified.
	cc_used_size	Size of the used code cache area when GC occurred. This information is output in units of kilobytes. This information is not output if the -XX:-PrintCodeCacheInfo option is specified.
	cc_max_size	Maximum size of the code cache area. This information is output in units of kilobytes. This information is not output if the -XX:-PrintCodeCacheInfo option is specified.
	cc_info	Maintenance information. This information is not output if the -XX:-PrintCodeCacheInfo option is specified.
Log entry related to concurrent marking	id	VCM (Java VM log file identifier)
	date	Start date and time of Concurrent Marking. This information is not output if the -XX:-HitachiVerboseGCPrintDate option is specified.
	cm_event	Status of Concurrent Marking. Concurrent Root Region Scan Start The Concurrent Root Region Scan started. Concurrent Root Region Scan End The Concurrent Root Region Scan ended. Concurrent Mark Start The Concurrent Mark started. Concurrent Mark End The Concurrent Mark ended. Concurrent Mark Stop The Concurrent Mark stopped. Concurrent Cleanup Start The Concurrent Cleanup started. Concurrent Cleanup End The Concurrent Cleanup ended.
	user_cpu	Total CPU time that all GC threads spent in user mode. This information is output in units of seconds. If acquisition of the CPU time fails, unknown is displayed, as in "[User: unknown]". This information is not output if the -XX:-HitachiVerboseGCCpuTime option is specified. If the status of the Concurrent Marking is Concurrent Mark Start, 0 is output.
	sys_cpu	Total CPU time that all GC threads spent in kernel mode. This information is output in units of seconds. If acquisition of the CPU time fails, unknown is displayed, as in "[Sys: unknown]". This information is not output if the -XX:-HitachiVerboseGCCpuTime option is specified. If the status of the Concurrent Marking is Concurrent Mark Start, 0 is output.

#

The size is estimated by rounding up the area size to the size of one region, and represented as a multiple of the size of one region.

The GC factor numbers output to cause_info are as follows.

Table 7‒3: List of GC causes

Cause number	Cause content	Description	GC type
			Other than G1GC	G1GC
0	ObjAllocFail	GC occurred because the object area could not be allocated.	Y	Y
1	System.gc	GC occurred because the java.lang.System.gc method was called.	Y	Y
3	DelayedGC	GC that was suspended by JNI or JVMTI was started.	Y	Y
4	JavaGCCommand	GC occurred due to the javagc command.	Y	Y
6	JHeapProfCommand	GC occurred due to the jheapprof command.	Y	N
8	EMReclaimFail	Because objects were moved to the Java heap due to explicit release of Explicit memory, the Java heap overflowed.	Y	N
9	EMMigrateFail	Because objects were moved to the Java heap due to automatic release of Explicit memory, the Java heap overflowed.	Y	N
10	JVMTIForceGC	GC occurred due to the JVMTI function ForceGarbageCollection().	Y	Y
11	PromotionFail	GC occurred due to a CopyGC promotion failure.	Y	N
12	EMJavaGCCommand	GC occurred because an Explicit memory block was released by the javagc command.	Y	Y
13	EHeapProfCommand	GC occurred due to the eheapprof command.	Y	Y
14	G1HumAllocFail	When G1GC was used, GC occurred because a Humongous area was allocated.	N	Y
15	G1EvacuationPause	An evacuation occurred when G1GC was used.	N	Y
16	Concurrent Marking	No GC occurred but the Concurrent Marking processing, which stops and executes applications, was logged.	N	Y
17	EvacuationFail	When G1GC was used, GC occurred due to an evacuation failure.	N	Y
18	MetaspaceAllocFail	GC occurred because the Metaspace area could not be allocated.	Y	Y
19	LastMetaspaceGC	The last GC occurred before a Metaspace OutOfMemory error occurred.	Y	Y

Legend:

Y: Output.

N: Not output.

Syntax

-XX:[+|-]HitachiCommaVerboseGC

Specifiable values

Type: String

-XX:+HitachiCommaVerboseGC

Outputs the extended verbosegc information delimited by commas, so that the information can be imported to a CSV format file.

All parentheses (), square brackets [], angle brackets <>, and colons (:) in the extended verbosegc information are deleted, and the resulting information in which values and character strings are delimited by commas (,) is output.

-XX:-HitachiCommaVerboseGC

The extended verbosegc information is output in a normal format.

Default value

If the definition item is omitted:

-XX:-HitachiCommaVerboseGC