We have two production clusters, and we don't on either. We also have days and days worth of no CMF reported.
Here is my config that works great for us: export HBASE_OPTS="$HBASE_OPTS -XX:+UseConcMarkSweepGC -XX:MaxDirectMemorySize=2G" # Uncomment below to enable java garbage collection logging. export HBASE_OPTS="$HBASE_OPTS -verbose:gc -Xms12000m -XX:CMSInitiatingOccupancyFraction=70 -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+HeapDumpOnOutOfMemoryError -Xloggc:$HBASE_HOME/logs/gc-hbase.log \ -XX:MaxTenuringThreshold=15 -XX:SurvivorRatio=8 \ -XX:+UseParNewGC \ -XX:NewSize=128m -XX:MaxNewSize=128m \ -XX:+CMSParallelRemarkEnabled \ -XX:-TraceClassUnloading " Also, just reduce the size of your RAM flushes to minimum, we are running on 0.19 and 0.20 for lower to high memstore limits, so our flushes are usually small enough not to cause major fragmentation issues. -Jack On Mon, Jun 6, 2011 at 10:24 AM, Stack <st...@duboce.net> wrote: > On Mon, Jun 6, 2011 at 10:06 AM, Wayne <wav...@gmail.com> wrote: >> I had 25 sec CMF failure this morning...looks like bulk inserts are required >> along with possibly weekly/daily scheduled rolling restarts. Do most >> production clusters run rolling restarts on a regular basis to give the JVM >> a fresh start? >> > > We don't do it (maybe we should!). Here is our bit of doc. on the > decommission script: http://hbase.apache.org/book/decommission.html > Its been working well for us; i.e. config. changes and upgrades while > under load. > > St.Ack >
