Do you see any exceptions in the Cassandra log?

Jun
IBM Almaden Research Center
K55/B1, 650 Harry Road, San Jose, CA 95120-6099

junrao@almaden.ibm.com


Inactive hide details for Brian Frank Cooper ---08/18/2009 03:37:40 PM---Hi folks, I have been loading a 6-server Cassandra cluBrian Frank Cooper ---08/18/2009 03:37:40 PM---Hi folks, I have been loading a 6-server Cassandra cluster with 1KB records. After a few million ins


From:

Brian Frank Cooper <cooperb@yahoo-inc.com>

To:

"cassandra-user@incubator.apache.org" <cassandra-user@incubator.apache.org>

Date:

08/18/2009 03:37 PM

Subject:

Anybody experience one Cassandra server locking up?





Hi folks,

I have been loading a 6-server Cassandra cluster with 1KB records. After a few million inserts, the insert rate drops dramatically. After investigation, one of the Cassandra servers seems to be in a bad state, using 100% of one core on an 8-core machine, and 0% on the other cores. Inserts to this box have completely stopped, and the inserts to the other boxes have slowed way down (more than a factor of 10 slower.) A “kill” or “kill -3” to the bad java process does nothing; I have to use “kill -9” to stop it. Has anybody experienced anything like this?

Additional info:

The servers are 8 core, 8GB servers. I am running 64 bit java 1.6, and here are the JVM options:

# Arguments to pass to the JVM
JVM_OPTS=" \
-ea \
-Xdebug \
-Xrunjdwp:transport=dt_socket,server=y,address=8888,suspend=n \
-Xms128M \
-Xmx6G \
-XX:SurvivorRatio=8 \
-XX:TargetSurvivorRatio=90 \
-XX:+AggressiveOpts \
-XX:+UseParNewGC \
-XX:+UseConcMarkSweepGC \
-XX:CMSInitiatingOccupancyFraction=1 \
-XX:+CMSParallelRemarkEnabled \
-XX:+HeapDumpOnOutOfMemoryError \
-Dcom.sun.management.jmxremote.port=8080 \
-Dcom.sun.management.jmxremote.ssl=false \
-Dcom.sun.management.jmxremote.authenticate=false"

(standard options from the Cassandra distribution, except for the 6GB of heap space.)

Replication factor is 1 (this is just a test, not a production setup) and memtable size is set to 1GB.

Thanks…

brian