incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From srmore <comom...@gmail.com>
Subject Cassandra Heap Size for data more than 1 TB
Date Wed, 02 Oct 2013 04:34:48 GMT
Does anyone know what would roughly be the heap size for cassandra with 1TB
of data ? We started with about 200 G and now on one of the nodes we are
already on 1 TB. We were using 8G of heap and that served us well up until
we reached 700 G where we started seeing failures and nodes flipping.

With 1 TB of data the node refuses to come back due to lack of memory.
needless to say repairs and compactions takes a lot of time. We upped the
heap from 8 G to 12 G and suddenly everything started moving rapidly i.e.
the repair tasks and the compaction tasks. But soon (in about 9-10 hrs) we
started seeing the same symptoms as we were seeing with 8 G.

So my question is how do I determine what is the optimal size of heap for
data around 1 TB ?

Following are some of my JVM settings

-Xms8G
-Xmx8G
-Xmn800m
-XX:NewSize=1200M
XX:MaxTenuringThreshold=2
-XX:SurvivorRatio=4

Thanks !

Mime
View raw message