What version of cassandra are you using ? What are the JVM settings? (check with ps aux | grep cassandra)
OOM in cassandra 1.2+ is rare but there is also https://issues.apache.org/jira/browse/CASSANDRA-5706 and https://issues.apache.org/jira/browse/CASSANDRA-6087 > One instance of "org.apache.cassandra.db.ColumnFamilyStore" loaded by > "sun.misc.Launcher$AppClassLoader @ 0x613e1bdc8" occupies 984,094,664 > (11.64%) bytes. 938MB is a bit of memory, the CFS and data tracker are dealing with the memtable. This may indicate things are not being flushed from memory correctly. > •java.lang.Thread @ 0x73e1f74c8 CompactionExecutor:158 - 839,225,000 (9.92%) > bytes. > •java.lang.Thread @ 0x717f08178 MutationStage:31 - 809,909,192 (9.58%) bytes. > •java.lang.Thread @ 0x717f082c8 MutationStage:5 - 649,667,472 (7.68%) bytes. > •java.lang.Thread @ 0x717f083a8 MutationStage:21 - 498,081,544 (5.89%) bytes. > •java.lang.Thread @ 0x71b357e70 MutationStage:11 - 444,931,288 (5.26%) bytes. maybe very big rows and/or very big mutations. hope that helps. ----------------- Aaron Morton New Zealand @aaronmorton Co-Founder & Principal Consultant Apache Cassandra Consulting http://www.thelastpickle.com On 15/11/2013, at 12:34 pm, Mike Koh <defmike...@gmail.com> wrote: > I am investigating Java Out of memory heap errors. So I created an .hprof > file and loaded it into Eclipse Memory Analyzer Tool which gave some "Problem > Suspects". > > First one looks like: > ---- > One instance of "org.apache.cassandra.db.ColumnFamilyStore" loaded by > "sun.misc.Launcher$AppClassLoader @ 0x613e1bdc8" occupies 984,094,664 > (11.64%) bytes. The memory is accumulated in one instance of > "org.apache.cassandra.db.DataTracker$View" loaded by > "sun.misc.Launcher$AppClassLoader @ 0x613e1bdc8". > ---- > > If I click around into the verbiage, I believe I can pick out the name of a > column family but that is about it. Can someone explain what the above means > in more detail and if it is indicative of a problem? > > > Next one looks like: > ----- > •java.lang.Thread @ 0x73e1f74c8 CompactionExecutor:158 - 839,225,000 (9.92%) > bytes. > •java.lang.Thread @ 0x717f08178 MutationStage:31 - 809,909,192 (9.58%) bytes. > •java.lang.Thread @ 0x717f082c8 MutationStage:5 - 649,667,472 (7.68%) bytes. > •java.lang.Thread @ 0x717f083a8 MutationStage:21 - 498,081,544 (5.89%) bytes. > •java.lang.Thread @ 0x71b357e70 MutationStage:11 - 444,931,288 (5.26%) bytes. > ------ > If I click into the verbiage, they above Compaction and Mutations all seem to > be referencing the same column family. Are the above related? Is there a way > I can tell more exactly what is being compacted and/or mutated more > specifically than which column family?
