I edited Peter Schuller's reply last time this came up into a FAQ: http://wiki.apache.org/cassandra/FAQ#mmap
On Wed, Mar 9, 2011 at 11:10 AM, Casey Deccio <ca...@deccio.net> wrote: > On Sat, Mar 5, 2011 at 7:37 PM, aaron morton <aa...@thelastpickle.com> > wrote: >> >> There is some additional memory usage in the JVM beyond that Heap size, in >> the permanent generation. 900mb sounds like too much for that, but you can >> check by connecting with JConsole and looking at the memory tab. You can >> also check the heap size there to see that it's under the value you've set. > > Thanks for the tip! > > From JConsole: > Heap memory usage: Current 46M; Max 902M > Non-Heap memory usage: Current 34M; Max 200MB > > Both of these seem reasonable and don't reach the (current) 2.1 GB resident > usage I am seeing. > >> Check you are using standard disk access (in conf/cassandra.yaml) rather >> than memory mapped access. However the memory mapped memory is reported as >> virtual memory, not resident. So I'm just mentioning it to be complete. > > At the moment, it's set to "auto", but it's a 64-bit machine, so I believe > it's using memory mapped. The virtual memory usage says that it is 54.6 GB. > >> If you think you've configured things correctly and the JVM is not >> behaving (which is unlikely) please include some information on the JVM and >> OS versions and some hard numbers about what the process is using. > > Debian 6.0 using openjdk-6-jre-lib-6b18-1.8.3-2+squeeze1 > > Thanks for your help. > > Casey > -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of DataStax, the source for professional Cassandra support http://www.datastax.com
