我有一个 AIX 服务器，使用 gencon GC 策略运行具有 8 GB 堆的 JVM 进程。今天我有 5 秒的暂停时间，这令人担忧。我查看了 GC 日志中的事件，但无法弄清楚所有时间都花在哪里了。
<con event="collection" id="1" timestamp="Oct 22 13:34:10 2015" intervalms="0.000"> <time exclusiveaccessms="0.195" /> <nursery freebytes="871692288" totalbytes="966367232" percent="90" /> <tenured freebytes="375809024" totalbytes="7516192768" percent="4" >
<soa freebytes="0" totalbytes="7140383744" percent="0" />
<loa freebytes="375809024" totalbytes="375809024" percent="100" /> </tenured> <stats tracetarget="2430736896">
<traced total="2804446392" mutators="2591437504" helpers="213008888" percent="115" />
<cards cleaned="1874" kickoff="102056216" /> </stats> <con event="remembered set scan">
<stats objectsfound="17649" traced="110458224" timetakenms="129.797" /> </con> <con event="final card cleaning">
<stats cardscleaned="334" traced="9118008" durationms="7.732" /> </con> <gc type="global" id="1" totalid="929" intervalms="0.000">
<classloadersunloaded count="162267" timetakenms="4957.805" />
<refs_cleared soft="1942" threshold="32" weak="164659" phantom="0" />
<finalization objectsqueued="120" />
***<timesms mark="258.390" sweep="33.125" compact="0.000" total="5267.373" />***
<nursery freebytes="904360200" totalbytes="966367232" percent="93" />
<tenured freebytes="3848182720" totalbytes="7516192768" percent="51" >
<soa freebytes="3472373696" totalbytes="7140383744" percent="48" />
<loa freebytes="375809024" totalbytes="375809024" percent="100" />
</tenured> </gc> <nursery freebytes="904360200" totalbytes="966367232" percent="93" /> <tenured freebytes="3848182720" totalbytes="7516192768" percent="51" >
<soa freebytes="3472373696" totalbytes="7140383744" percent="48" />
<loa freebytes="375809024" totalbytes="375809024" percent="100" /> </tenured> <time totalms="5406.538" /> </con>
如何找到完整 GC 的哪个 Activity 部分占用了大部分暂停时间？
谢谢
最佳答案
扫描类加载器所花费的时间不计入总时间:
<classloadersunloaded count="162267" timetakenms="4957.805" />
内存中有 162267 个类加载器，扫描需要 4957.805 毫秒。这似乎是已知问题，解决方法和修复如下:http://www-01.ibm.com/support/docview.wss?uid=swg1IZ76742
关于java - GC 暂停 5 秒，但标记、扫描和压缩耗时不到 1 秒，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/33281313/