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From: Jonathan Ellis <jbellis@gmail.com>
Date: Fri, 18 Nov 2011 17:15:39 -0600
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Subject: Re: ParNew and caching
To: user@cassandra.apache.org
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No i/o?  No sstable counts going up in cfhistograms?

Is the heap so full you're experiencing GC pressure that way?

On Fri, Nov 18, 2011 at 3:46 PM, Todd Burruss <bburruss@expedia.com> wrote:
> Ok, I figured something like that. =A0Switching to
> ConcurrentLinkedHashCacheProvider I see it is a lot better, but still
> instead of the 25-30ms response times I enjoyed with no caching, I'm
> seeing 500ms at 100% hit rate on the cache. =A0No old gen pressure at all=
,
> just ParNew crazy.
>
> More info on my use case is that I am picking 50 columns from the 70k.
> Since the whole row is in the cache, and no copying from off-heap nor dis=
k
> buffers, seems like it should be faster than non-cache mode.
>
> More thoughts :)

--=20
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of DataStax, the source for professional Cassandra support
http://www.datastax.com