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The "MemtableThresholds" page has been changed by FlipKromer. http://wiki.apache.org/cassandra/MemtableThresholds?action=diff&rev1=18&rev2=19 -------------------------------------------------- <<TableOfContents>> == Don't Touch that Dial == - The settings described here should only be changed in the face of a quantifiable performance problem. They will affect the cluster quite differently for distinct use cases and workloads, and the defaults were well-chosen. + The settings described here should only be changed in the face of a quantifiable performance problem. They will affect the cluster quite differently for distinct use cases and workloads, and the defaults, though conservative, were well-chosen. == JVM Heap Size == By default, the cassandra startup scripts specifies a maximum JVM heap of -Xmx1G. Consider increasing this -- but gently! If Cassandra and other processes take up too much of the available ram, they'll force out the operating system's file buffers and caches. These are as important as the internal data structures for ensuring Cassandra performance. @@ -45, +45 @@ ''Note: in version 0.7b2+, the value will be applied on a [[https://issues.apache.org/jira/browse/CASSANDRA-1007|per column-family basis]].'' - - == Using Jconsole To Optimize Thresholds == Cassandra's column-family mbeans have a number of attributes that can prove invaluable in determining optimal thresholds. One way to access this instrumentation is by using Jconsole, a graphical monitoring and management application that ships with your JDK.
