On 6/15/2016 3:05 PM, Cas Rusnov wrote: > After trying many of the off the shelf configurations (including CMS > configurations but excluding G1GC, which we're still taking the > warnings about seriously), numerous tweaks, rumors, various instance > sizes, and all the rest, most of which regardless of heap size and > newspace size resulted in frequent 30+ second STW GCs, we settled on > the following configuration which leads to occasional high GCs but > mostly stays between 10-20 second STWs every few minutes (which is > almost acceptable): -XX:+AggressiveOpts -XX:+UnlockDiagnosticVMOptions > -XX:+UseAdaptiveSizePolicy -XX:+UseLargePages -XX:+UseParallelGC > -XX:+UseParallelOldGC -XX:MaxGCPauseMillis=15000 -XX:MaxNewSize=12000m > -XX:ParGCCardsPerStrideChunk=4096 -XX:ParallelGCThreads=16 -Xms31000m > -Xmx31000m
You mentioned something called "HugeTable" ... I assume you're talking about huge pages. If that's what you're talking about, have you also turned off transparent huge pages? If you haven't, you might want to completely disable huge pages in your OS. There's evidence that the transparent option can affect performance. I assume you've probably looked at my GC info at the following URL: http://wiki.apache.org/solr/ShawnHeisey#GC_Tuning_for_Solr The parallel collector is most definitely not a good choice. It does not optimize for latency. It's my understanding that it actually prefers full GCs, because it is optimized for throughput. Solr thrives on good latency, throughput doesn't matter very much. If you want to continue avoiding G1, you should definitely be using CMS. My recommendation right now would be to try the G1 settings on my wiki page under the heading "Current experiments" or the CMS settings just below that. The out-of-the-box GC tuning included with Solr 6 is probably a better option than the parallel collector you've got configured now. Thanks, Shawn
