10/26/2017 Universal Java GC analysis tool - Java Garbage collection log analysis made easy

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1 Analysis Report GC log le: atlassian-jira-gc _0012.log.0.current Duration: 14 hrs 59 min 51 sec System Time greater than User Time In 25 GC event(s), 'sys' time is greater than 'usr' time. It's not a healthy sign. Timestamp User Time (secs) Sys Time (secs) Real Time (secs) T01:55: T03:01: T03:09: T03:16: T03:20: T03:23: T04:03: T04:06: T04:11: T04:18: T04:26: T04:33: T04:38: T05:00: T05:23: T05:25: T05:33: T06:00: T06:10: T06:31: T06:33: more events... Read our recommendations to reduce sys time ( 1/9

2 JVM Heap Size Generation Allocated Peak Young Generation 9.92 gb 9.6 gb Old Generation 6.08 gb 12.7 gb Meta Space 1.03 gb mb Young + Old + Meta space gb gb Key Performance Indicators (Important section of the report. To learn more about KPIs, click here ( 1 Throughput : % 2 Latency: Avg GC Time 77 ms Max GC Time 2 sec 870 ms GC Duration Time Range : Duration (secs) No. of GCs Percentage % % % 2/9

3 Interactive Graphs (All graphs are zoomable) 3/9

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7 G1 GC Statistics Young GC Concurrent Mark Cleanup Mixed Full GC Remark initial-mark Total 7/9

8 Count Total GC Time 3 min 5 sec 211 ms 0 1 sec 900 ms 18 sec 870 ms 290 ms 9 sec 460 ms 8 sec 710 ms 3 min 44 sec 441 ms Avg GC Time 73 ms 0 26 ms 170 ms 290 ms 131 ms 121 ms 77 ms Avg Time std dev 91 ms 0 9 ms 59 ms 0 44 ms 45 ms 90 ms Min/Max Time 0 / 2 sec 870 ms 0 / 0 0 / 70 ms 0 / 310 ms 0 / 290 ms 0 / 370 ms 0 / 280 ms 0 / 2 sec 870 ms Avg Interval Time 21 sec 357 ms 11 min 44 sec 806 ms 11 min 44 sec 808 ms 3 min 32 sec 746 ms n/a 11 min 44 sec 806 ms 11 min 44 sec 771 ms 1 min 34 sec 988 ms Object Stats (These are good metrics to include in your performance reports) Total created bytes tb Total promoted bytes gb Avg creation rate mb/sec Avg promotion rate 1.38 mb/sec Memory Leak No major memory leaks. (Note: there are 8 avours of OutOfMemoryErrors ( les.wordpress.com/2014/12/outofmemoryerror2.pdf). With GC Logs you can diagnose only 5 avours of them(java heap space, GC overhead limit exceeded, Requested array size exceeds VM limit, Permgen space, Metaspace). So in other words, your application could be still su ering from memory leaks, but need other tools to diagnose them, not just GC Logs.) Consecutive Full GC None. Long Pause None. Safe Point Duration (To learn more about SafePoint duration, click here ( Not Reported in the log. 8/9

9 GC Causes (What events caused the GCs, how much time it consumed?) Cause Count Avg Time Max Time Total Time Time % G1 Evacuation Pause ms 590 ms 2 min 45 sec 982 ms 73.95% Others 216 n/a n/a 55 sec 969 ms 24.94% GCLocker Initiated GC ms 240 ms 1 sec 720 ms 0.77% G1 Humongous Allocation 4 73 ms 90 ms 290 ms 0.13% Metadata GC Threshold 5 48 ms 80 ms 240 ms 0.11% Evacuation Failure 3 73 ms 80 ms 220 ms 0.1% System.gc() calls 1 20 ms 20 ms 20 ms 0.01% Total 2929 n/a n/a 3 min 44 sec 440 ms % Tenuring Summary Desired Survivor Size: mb, Max Threshold: 2 Age Survival Count Average size (kb) Average Total 'To' size (kb) age age Command Line Flags -XX:GCLogFileSize= XX:InitialHeapSize= XX:InitialTenuringThreshold=2 -XX:MaxHeapSize= XX:MaxTenuringThreshold=2 - XX:NumberOfGCLogFiles=5 -XX:-OmitStackTraceInFastThrow -XX:ParGCCardsPerStrideChunk= XX:+ParallelRefProcEnabled -XX:+PrintGC - XX:+PrintGCDateStamps -XX:+PrintGCDetails -XX:+PrintGCTimeStamps -XX:+PrintTenuringDistribution -XX:ReservedCodeCacheSize= /9