G1 Region size info
Gopal, Prasanna CWK
prasanna.gopal at blackrock.com
Wed Feb 8 12:25:49 UTC 2017
Hi All
I am trying to understand the region size info provided in of our application’s GC log file.
We are running an application with the following configuration
-Xmx7G
-Xms7G
-XX:+UseG1GC
-XX:+UnlockExperimentalVMOptions
-XX:InitiatingHeapOccupancyPercent=60
-XX:G1ReservePercent=20
-XX:G1ReservePercent=20
-XX:G1HeapRegionSize=32M
-XX:G1MixedGCLiveThresholdPercent=85
-XX:MaxGCPauseMillis=500
-XX:+ParallelRefProcEnabled
-XX:+PrintAdaptiveSizePolicy
-XX:+PrintHeapAtGC
-XX:+PrintReferenceGC
-XX:+PrintGCDateStamps
-XX:+PrintTenuringDistribution
-XX:+PrintGCApplicationConcurrentTime
-XX:+PrintGCApplicationStoppedTime
JDK : jdk_7u40_x64 ( Yes we need to move to latest JDK)
At the end of the region size info, we have following summary
### SUMMARY capacity: 352.00 MB used: 328.94 MB / 93.45 % prev-live: 138.65 MB / 39.39 % next-live: 0.00 MB / 0.00 %
4283M->4121M(6144M), 0.0066530 secs]
[Times: user=0.04 sys=0.00, real=0.01 secs]
2017-02-08T00:00:59.239-0500: 223238.232: Total time for which application threads were stopped: 0.0075650 seconds
2017-02-08T00:00:59.239-0500: 223238.232: [GC concurrent-cleanup-start]
2017-02-08T00:00:59.239-0500: 223238.232: [GC concurrent-cleanup-end, 0.0000950 secs]
2017-02-08T00:01:00.003-0500: 223238.996: Application time: 0.7639680 seconds
2017-02-08T00:01:00.005-0500: 223238.999: Total time for which application threads were stopped: 0.0025640 seconds
2017-02-08T00:01:05.024-0500: 223244.017: Application time: 5.0186280 seconds
Does this mean, our heap occupancy is only 352 MB after Post-Sorting phase ?. It doesn’t co-relate with the information provided at thd end of GC clean up phase (4283M->4121M(6144M), 0.0066530 secs) , which say the heap size is 4121M.
And subsequent Young GC shows the following heap composition
[Eden: 992.0M(992.0M)->0.0B(1088.0M) Survivors: 64.0M->32.0M Heap: 4538.0M(6144.0M)->3516.9M(6144.0M)]
Could you please help me in understanding the Summary information provided in Post sorting phase ? . Please let me know ,if you need any more information.
Regards
Prasanna
Region size info
=============
region size 32768K, 2 young (65536K), 2 survivors (65536K)
compacting perm gen total 98304K, used 85713K [0x00000007c0000000, 0x00000007c6000000, 0x0000000800000000)
the space 98304K, 87% used [0x00000007c0000000, 0x00000007c53b4400, 0x00000007c53b4400, 0x00000007c6000000)
No shared spaces configured.
}
[Times: user=0.09 sys=0.00, real=0.02 secs]
2017-02-08T00:00:55.746-0500: 223234.739: [GC concurrent-root-region-scan-start]
2017-02-08T00:00:55.746-0500: 223234.739: Total time for which application threads were stopped: 0.0145960 seconds
2017-02-08T00:00:55.748-0500: 223234.742: [GC concurrent-root-region-scan-end, 0.0025760 secs]
2017-02-08T00:00:55.748-0500: 223234.742: [GC concurrent-mark-start]
2017-02-08T00:00:59.211-0500: 223238.204: [GC concurrent-mark-end, 3.4626220 secs]
2017-02-08T00:00:59.211-0500: 223238.204: Application time: 3.4652490 seconds
2017-02-08T00:00:59.212-0500: 223238.205: [GC remark 2017-02-08T00:00:59.213-0500: 223238.206: [GC ref-proc2017-02-08T00:00:59.213-0500: 223238.206: [SoftReference, 986 refs, 0.0007480 secs]2017-02-08T00:00:59.213-0500: 223238.207: [WeakReference, 547 refs, 0.0004050 secs]2017-02-08T00:00:59.214-0500: 223238.207: [FinalReference, 1 refs, 0.0002350 secs]2017-02-08T00:00:59.214-0500: 223238.207: [PhantomReference, 6 refs, 0.0002730 secs]2017-02-08T00:00:59.214-0500: 223238.208: [JNI Weak Reference, 0.0000510 secs], 0.0018440 secs], 0.0189520 secs]
[Times: user=0.05 sys=0.00, real=0.02 secs]
2017-02-08T00:00:59.231-0500: 223238.225: Total time for which application threads were stopped: 0.0202670 seconds
2017-02-08T00:00:59.231-0500: 223238.225: Application time: 0.0001010 seconds
2017-02-08T00:00:59.232-0500: 223238.226: [GC cleanup
### PHASE Post-Marking @ 223238.226
### HEAP committed: 0x0000000640000000-0x00000007c0000000 reserved: 0x0000000640000000-0x00000007c0000000 region-size: 33554432
###
### type address-range used prev-live next-live gc-eff
### (bytes) (bytes) (bytes) (bytes/ms)
### OLD 0x0000000640000000-0x0000000642000000 32368376 32368376 32366752 223961.6
### OLD 0x0000000642000000-0x0000000644000000 33554408 33554408 33554408 21493.5
### OLD 0x0000000644000000-0x0000000646000000 33554424 33554424 33554424 29029.2
### OLD 0x0000000646000000-0x0000000648000000 33554424 33554424 33554424 13470.1
### OLD 0x0000000648000000-0x000000064a000000 33554432 33554432 33552752 293134.5
### OLD 0x000000064a000000-0x000000064c000000 33357104 33357104 33357104 179951.0
### OLD 0x000000064c000000-0x000000064e000000 33554408 33554408 33554408 525436.5
### OLD 0x000000064e000000-0x0000000650000000 33554416 33554416 33554416 273501.1
### OLD 0x0000000650000000-0x0000000652000000 33554432 33554432 33554432 407703.2
### OLD 0x0000000652000000-0x0000000654000000 33554432 33554432 33554432 70645.8
### OLD 0x0000000654000000-0x0000000656000000 33554432 33554432 33554432 222200.0
### OLD 0x0000000656000000-0x0000000658000000 33554392 33554392 33554392 16195314.6
### OLD 0x0000000658000000-0x000000065a000000 33303600 33303600 33303600 428407.8
### OLD 0x000000065a000000-0x000000065c000000 33554424 33554424 33554424 153899.4
### OLD 0x000000065c000000-0x000000065e000000 33554384 33554384 33554384 307229.6
### OLD 0x000000065e000000-0x0000000660000000 33554416 33554416 33554416 10610494.9
### OLD 0x0000000660000000-0x0000000662000000 33554416 33554416 33554416 469683.0
### OLD 0x0000000662000000-0x0000000664000000 33554320 33554320 33554320 1241801.8
### OLD 0x0000000664000000-0x0000000666000000 33554416 33554416 33554416 371576.7
### OLD 0x0000000666000000-0x0000000668000000 33554432 33554408 33554408 18876.1
### OLD 0x0000000668000000-0x000000066a000000 33553800 33553800 33553800 197254.3
### OLD 0x000000066a000000-0x000000066c000000 32920592 32920592 32920592 261906.8
### OLD 0x000000066c000000-0x000000066e000000 33554272 33554272 33554272 263415.0
### OLD 0x000000066e000000-0x0000000670000000 33466704 33466704 33466704 217406.7
### OLD 0x0000000670000000-0x0000000672000000 33554432 33554432 33554432 558273.8
### OLD 0x0000000672000000-0x0000000674000000 33554424 33554424 33521640 471863.4
### OLD 0x0000000674000000-0x0000000676000000 33554416 33554416 33554416 24962.1
### OLD 0x0000000676000000-0x0000000678000000 32866480 32866480 32866480 469198.9
### OLD 0x0000000678000000-0x000000067a000000 33554424 33554424 33554424 1911056.3
### OLD 0x000000067a000000-0x000000067c000000 33420736 33420736 33420736 405214.5
### OLD 0x000000067c000000-0x000000067e000000 33554432 33554432 33554432 413762.1
### OLD 0x000000067e000000-0x0000000680000000 33554144 33554144 33554144 658142.1
### OLD 0x0000000680000000-0x0000000682000000 33554432 33554432 33554432 561025.9
### OLD 0x0000000682000000-0x0000000684000000 33554248 33554248 33543904 702743.4
### OLD 0x0000000684000000-0x0000000686000000 33554416 33554416 33554416 4785040.9
### OLD 0x0000000686000000-0x0000000688000000 33554360 33554360 33554360 307205.2
### OLD 0x0000000688000000-0x000000068a000000 33554416 33554416 33554416 791487.3
### OLD 0x000000068a000000-0x000000068c000000 33554376 33554376 33554376 6024807.6
…… Remove some for brevity
### HUMS 0x000000079e000000-0x00000007a0000000 33554432 33554432 33554432 501904008.8
### HUMC 0x00000007a0000000-0x00000007a2000000 2367536 2367536 2367536 2526909.9
### FREE 0x00000007a2000000-0x00000007a4000000 0 0 0 1018023826.2
### FREE 0x00000007a4000000-0x00000007a6000000 0 0 0 3621347.9
### FREE 0x00000007a6000000-0x00000007a8000000 0 0 0 6975354.2
### FREE 0x00000007a8000000-0x00000007aa000000 0 0 0 6228744.7
### FREE 0x00000007aa000000-0x00000007ac000000 0 0 0 825510.3
### FREE 0x00000007ac000000-0x00000007ae000000 0 0 0 3304768.5
### FREE 0x00000007ae000000-0x00000007b0000000 0 0 0 2701625.1
### FREE 0x00000007b0000000-0x00000007b2000000 0 0 0 2623840.5
### FREE 0x00000007b2000000-0x00000007b4000000 0 0 0 6313095.1
### FREE 0x00000007b4000000-0x00000007b6000000 0 0 0 4588159.0
### FREE 0x00000007b6000000-0x00000007b8000000 0 0 0 2184971.5
### FREE 0x00000007b8000000-0x00000007ba000000 0 0 0 592114.6
### FREE 0x00000007ba000000-0x00000007bc000000 0 0 0 24307488.7
### FREE 0x00000007bc000000-0x00000007be000000 0 0 0 2283212.1
### FREE 0x00000007be000000-0x00000007c0000000 0 0 0 627031.8
###
### SUMMARY capacity: 6144.00 MB used: 4283.18 MB / 69.71 % prev-live: 4057.87 MB / 66.05 % next-live: 3896.51 MB / 63.42 %
### PHASE Post-Sorting @ 223238.232
### HEAP committed: 0x0000000640000000-0x00000007c0000000 reserved: 0x0000000640000000-0x00000007c0000000 region-size: 33554432
###
### type address-range used prev-live next-live gc-eff
### (bytes) (bytes) (bytes) (bytes/ms)
### OLD 0x0000000736000000-0x0000000738000000 33554432 2166312 0 87829788.1
### OLD 0x000000073c000000-0x000000073e000000 33554432 6048552 0 26417453.7
### OLD 0x000000073a000000-0x000000073c000000 33554432 13552368 0 8930752.6
### OLD 0x00000006fe000000-0x0000000700000000 32982728 15474224 0 6200283.7
### OLD 0x0000000738000000-0x000000073a000000 33554432 17669672 0 5731058.5
### OLD 0x00000006f0000000-0x00000006f2000000 33232096 5230584 0 5595398.5
### OLD 0x00000006f2000000-0x00000006f4000000 33554384 8938848 0 5331392.0
### OLD 0x0000000706000000-0x0000000708000000 10273584 10273432 0 3376131.8
### OLD 0x00000006ee000000-0x00000006f0000000 33554392 18481472 0 1231822.2
### OLD 0x00000006f6000000-0x00000006f8000000 33554432 22116128 0 774360.6
### OLD 0x0000000702000000-0x0000000704000000 33554424 25431376 0 520416.9
###
### SUMMARY capacity: 352.00 MB used: 328.94 MB / 93.45 % prev-live: 138.65 MB / 39.39 % next-live: 0.00 MB / 0.00 %
4283M->4121M(6144M), 0.0066530 secs]
[Times: user=0.04 sys=0.00, real=0.01 secs]
2017-02-08T00:00:59.239-0500: 223238.232: Total time for which application threads were stopped: 0.0075650 seconds
2017-02-08T00:00:59.239-0500: 223238.232: [GC concurrent-cleanup-start]
2017-02-08T00:00:59.239-0500: 223238.232: [GC concurrent-cleanup-end, 0.0000950 secs]
2017-02-08T00:01:00.003-0500: 223238.996: Application time: 0.7639680 seconds
2017-02-08T00:01:00.005-0500: 223238.999: Total time for which application threads were stopped: 0.0025640 seconds
2017-02-08T00:01:05.024-0500: 223244.017: Application time: 5.0186280 seconds
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