2011/3/23 ruslan usifov <ruslan.usi...@gmail.com> > Hello > > Sometimes i seen in gc log follow message: > > 2011-03-23T14:40:56.049+0300: 14897.104: [GC 14897.104: [ParNew (promotion > failed) > Desired survivor size 41943040 bytes, new threshold 2 (max 2) > - age 1: 5573024 bytes, 5573024 total > - age 2: 5064608 bytes, 10637632 total > : 672577K->670749K(737280K), 0.1837950 secs]14897.288: [CMS: > 1602487K->779310K(2326528K), 4.7525580 secs] 2270940K->779310K(3063808K), [ > CMS Perm : 20073K->19913K(33420K)], 4.9365810 secs] [Times: user=5.06 > sys=0.00, real=4.93 secs] > Total time for which application threads were stopped: 4.9378750 seconds >
After investigations i detect that this happens when Memtableflash and compact happens. So at this moment young part of heap is overflown and Full GC happens. So to resolve this i must tune young generation (HEAP_NEWSIZE) -Xmn, and tune in_memory_compaction_limit_in_mb config parameter? Also if memtables flushes due "memtable_flush_after" if i separate in time memtable flushes can this helps?
