1
我想调整我的应用程序的响应能力,最大允许的GC暂停是40毫秒。无法理解为何这种停顿需要大约900毫秒的时间。应用程序是旨在服务于高QPS的低延迟应用程序。G1垃圾回收器长暂停不知道
GC PARAMS:-Xmx5G -XX:+ UseG1GC -XX:MaxGCPauseMillis = 40
日志:
2014-10-02T16:31:08.508+0530: 2072.186: [GC pause (young)
Desired survivor size 148373504 bytes, new threshold 15 (max 15)
- age 1: 10600184 bytes, 10600184 total
- age 2: 67024 bytes, 10667208 total
- age 3: 44560 bytes, 10711768 total
- age 4: 3520 bytes, 10715288 total
- age 5: 4080 bytes, 10719368 total
- age 6: 4464 bytes, 10723832 total
- age 7: 2568 bytes, 10726400 total
- age 8: 4872 bytes, 10731272 total
- age 9: 3216 bytes, 10734488 total
- age 10: 2400 bytes, 10736888 total
- age 11: 2024 bytes, 10738912 total
- age 12: 3144 bytes, 10742056 total
- age 13: 8584 bytes, 10750640 total
- age 14: 2672 bytes, 10753312 total
- age 15: 696 bytes, 10754008 total
, 0.0384210 secs]
[Parallel Time: 15.2 ms, GC Workers: 15]
[GC Worker Start (ms): Min: 2072186.5, Avg: 2072186.5, Max: 2072186.6, Diff: 0.1]
[Ext Root Scanning (ms): Min: 1.0, Avg: 1.0, Max: 1.1, Diff: 0.1, Sum: 15.2]
[Update RS (ms): Min: 0.3, Avg: 0.4, Max: 0.4, Diff: 0.1, Sum: 5.7]
[Processed Buffers: Min: 1, Avg: 3.3, Max: 5, Diff: 4, Sum: 49]
[Scan RS (ms): Min: 0.5, Avg: 0.5, Max: 0.6, Diff: 0.1, Sum: 7.8]
[Code Root Scanning (ms): Min: 0.0, Avg: 0.0, Max: 0.0, Diff: 0.0, Sum: 0.3]
[Object Copy (ms): Min: 12.8, Avg: 12.9, Max: 13.0, Diff: 0.2, Sum: 193.0]
[Termination (ms): Min: 0.1, Avg: 0.1, Max: 0.1, Diff: 0.1, Sum: 1.7]
[GC Worker Other (ms): Min: 0.0, Avg: 0.1, Max: 0.2, Diff: 0.1, Sum: 1.4]
[GC Worker Total (ms): Min: 14.9, Avg: 15.0, Max: 15.1, Diff: 0.2, Sum: 225.1]
[GC Worker End (ms): Min: 2072201.5, Avg: 2072201.5, Max: 2072201.6, Diff: 0.1]
[Code Root Fixup: 0.2 ms]
[Code Root Migration: 0.6 ms]
[Clear CT: 0.8 ms]
[Other: 21.6 ms]
[Choose CSet: 0.0 ms]
[Ref Proc: 14.2 ms]
[Ref Enq: 0.6 ms]
[Free CSet: 6.6 ms]
[Eden: 2244.0M(2244.0M)->0.0B(2571.0M) Survivors: 19.0M->10.0M Heap: 2443.7M(5120.0M)->191.4M(5120.0M)]
[Times: user=0.26 sys=0.00, real=0.90 secs]
2014-10-02T16:31:09.406+0530: 2073.085: Total time for which application threads were stopped: 0.8992240 seconds
Java的版本:
Java版本 “1.7.0_60”
的Java( TM)SE运行时环境(内部版本1.7.0_60-b19)
Java HotSpot™64位服务器虚拟机(版本24.60-b09,混合模式)
请帮助我o明白是什么造成了这么长时间的停顿?以及如何预防它?
感谢您的回答!内存交换是不可能的,我们在机器上有更多的免费ram。我如何确定究竟是什么造成了这种情况?我检查了萨尔值,没有发现有关系 – 2014-10-03 10:51:03
可悲的是我不知道如何进一步缩小它。您可以尝试不同的机器并观察其行为是否有所不同。如果你知道是什么导致了这种行为,我会非常高兴。 – snowdragon 2014-10-06 12:23:53