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From Yang <teddyyyy...@gmail.com>
Subject Re: what is taking up my JVM heap space?
Date Fri, 05 Aug 2011 03:20:40 GMT
Thanks Jonathan


On Thu, Aug 4, 2011 at 7:44 PM, Jonathan Ellis <jbellis@gmail.com> wrote:
> If you didn't GC post-flush then it's just leftovers.
>
> An "empty" Cassandra (nothing in memtables or cache) will use 5-10MB of heap.
>
> On Thu, Aug 4, 2011 at 9:38 PM, Yang <teddyyyy123@gmail.com> wrote:
>> I ran my cassandra cluster on one node, inserted about 500000 rows,
>> each about 400 bytes, then the heap went up to 800MB, and constantly
>> goes into full GC. I guessed that the memtable was probably taking a
>> lot of space, so I did a node tool flush, so that
>> all memtable are changed to 0. after this, the heap came down a bit,  to 500MB.
>>
>> but I thought it should be close to 0 right after the flush?? or else
>> what is taking up the space?
>> I'm still trying to look at the hprof file to figure out, but it seems
>> difficult too
>>
>>
>> Thanks
>> Yang
>>
>
>
>
> --
> Jonathan Ellis
> Project Chair, Apache Cassandra
> co-founder of DataStax, the source for professional Cassandra support
> http://www.datastax.com
>

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