java - GC pauses of 5 seconds but mark, sweep and compact take less than 1 second -
i have aix server running jvm process 8 gb heap using gencon gc policy. today had 5s pause time concerning. looked @ event in gc log couldn't figure out time spent.
<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>
how can find activity part of full gc taking bulk of pause time?
thanks
time taken scan of class loaders not accounted in total:
<classloadersunloaded count="162267" timetakenms="4957.805" />
you have 162267 class loaders in memory taking 4957.805ms scan. seems known problem, workaround , fix here: http://www-01.ibm.com/support/docview.wss?uid=swg1iz76742
Comments
Post a Comment