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From Dikang Gu <dikan...@gmail.com>
Subject Re: How to reduce the Read Latency.
Date Fri, 20 May 2011 08:32:14 GMT
I use the default consistency level in the hector client, so it should be QUORUM.

-- 
Dikang Gu
0086 - 18611140205
On Friday, May 20, 2011 at 4:25 PM, Jeffrey Kesselman wrote: 
> What consistency are you asking for?
> 
> On Fri, May 20, 2011 at 7:42 AM, Dikang Gu <dikang85@gmail.com> wrote:
> > Hi All,
> > I'm running three cassandra 0.7.4 nodes in a cluster, and I give 2G memory
> > to each node.
> > Now, I get the cfstats here:
> > Keyspace: UserMap
> > Read Count: 38411
> > Read Latency: 123.54214613001484 ms.
> > Write Count: 44155
> > Write Latency: 0.02341093873853471 ms.
> > Pending Tasks: 0
> > Column Family: Map
> > SSTable count: 3
> > Space used (live): 32704387
> > Space used (total): 32704387
> > Memtable Columns Count: 49
> > Memtable Data Size: 3348
> > Memtable Switch Count: 56
> > Read Count: 38411
> > Read Latency: 123.542 ms.
> > Write Count: 44155
> > Write Latency: 0.023 ms.
> > Pending Tasks: 0
> > Key cache capacity: 200000
> > Key cache size: 611
> > Key cache hit rate: 0.9294361241314483
> > Row cache: disabled
> > Compacted row minimum size: 125
> > Compacted row maximum size: 17436917
> > Compacted row mean size: 147647
> > You can find that the Read Latency is really high here, so what can I do to
> > reduce the latency? Give more memory to the three nodes? Any other options?
> > Thanks.
> > --
> > Dikang Gu
> > 0086 - 18611140205
> 
> 
> 
> -- 
> It's always darkest just before you are eaten by a grue.
> 

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