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 <CADJL=w4v1vUaQoH7aXDm5fhJjoFxa3=1+qM1EOZydg=82cJPcA@mail.gmail.com>
Date: Sat, 10 Mar 2012 13:50:19 -0800
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 <CAO5xsd0h497TtPsrbEcmRBZO-TEh6HNxx-_4vZje8KdG2xec0w@mail.gmail.com>
Subject: Re: LeveledCompaction and/or SnappyCompressor causing memory pressure
 during repair
From: Peter Schuller <peter.schuller@infidyne.com>
To: user@cassandra.apache.org
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> However, when I run a repair my CMS usage graph no longer shows sudden drops
> but rather gradual slopes and only manages to clear around 300MB each GC.
> This seems to occur on 2 other nodes in my cluster around the same time, I
> assume this is because they're the replicas (we use 3 replicas). Parnew
> collections look about the same on my graphs with or without repair running
> so no trouble there so far as I can tell.

I don't know why leveled/snappy would affect it, but disregarding
that, I would have been suggesting that you are seeing additional heap
usage because of long-running repairs retaining sstables and delaying
their unload/removal (index sampling/bloom filters filling your heap).
If it really only happens for leveled/snappy however, I don't know
what that might be caused by.

-- 
/ Peter Schuller (@scode, http://worldmodscode.wordpress.com)