cassandra-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Peter Schuller <>
Subject Re: [SOLVED] Very high memory utilization (not caused by mmap on sstables)
Date Sun, 19 Dec 2010 12:57:33 GMT
> victor@****:~$ sudo ps aux | grep "cassandra"
> cassandra     11034  0.2 22.9 1107772 462764 ?      Sl   Dec17   6:13
> /usr/bin/java -ea -Xms128M -Xmx512M -XX:+UseParNewGC -XX:+UseConcMarkSweepGC
> -XX:+CMSParallelRemarkEnabled -XX:SurvivorRatio=8 -XX:MaxTenuringThreshold=1
> -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly
> -XX:+HeapDumpOnOutOfMemoryError
> -Dstorage-config=bin/../conf -Dcassandra-foreground=yes -cp
> bin/../conf:bin/../build/classes:bin/../lib/antlr-3.1.3.jar:bin/../lib/apache-cassandra-0.6.6.jar:bin/../lib/clhm-production.jar:bin/../lib/commons-cli-1.1.jar:bin/../lib/commons-codec-1.2.jar:bin/../lib/commons-collections-3.2.1.jar:bin/../lib/commons-lang-2.4.jar:bin/../lib/google-collections-1.0.jar:bin/../lib/hadoop-core-0.20.1.jar:bin/../lib/high-scale-lib.jar:bin/../lib/ivy-2.1.0.jar:bin/../lib/jackson-core-asl-1.4.0.jar:bin/../lib/jackson-mapper-asl-1.4.0.jar:bin/../lib/jline-0.9.94.jar:bin/../lib/json-simple-1.1.jar:bin/../lib/libthrift-r917130.jar:bin/../lib/log4j-1.2.14.jar:bin/../lib/slf4j-api-1.5.8.jar:bin/../lib/slf4j-log4j12-1.5.8.jar
> org.apache.cassandra.thrift.CassandraDaemon
> Cassandra uses 462764 Kb, roughly 460 Mb for 2 Mb of data... And it keeps
> getting bigger.
> It is important to know that I have just a few insert, quite a lot of read
> though. Also Cassandra seams to completly ignore the JVM limitations such as
> Xmx.
> If I don't stop and launch Cassandra every 15 ou 20 days it simply crashes,
> due to oom errors.

The resident size is not unexpected given that your Xmx is 512 MB. The
virtual may or may not be expected depending; for example thread
stacks as previously discussed in this thread.

If you're not seeing the *resident* set size go above the maximum heap
size, you're unlikely to be seeing the same problem.

WIth respect to OOM, see - but without more
information it's difficult to know what specifically it is that you're
hitting. Are you seriously saying you're running for 15-20 days with
only 2 mb of live data?

/ Peter Schuller

View raw message