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From aaron morton <aa...@thelastpickle.com>
Subject Re: slow read
Date Mon, 05 Mar 2012 10:33:17 GMT
Where is the client running from ? 

To see if a node it keeping up with requests look at nodetool tpstats, check if the read stage
is backing up. 

To see how long a read takes, use nodetool cfstats and look at the read latency. (this the
latency of a read on that node, not cluster wide)

To see how long a read takes cluster wide, use the StorageProxyMBean via JConsole. 

Hope that helps. 

-----------------
Aaron Morton
Freelance Developer
@aaronmorton
http://www.thelastpickle.com

On 5/03/2012, at 10:46 PM, ruslan usifov wrote:

> And sum of all rq/s threads is 160?? 
> 
> 2012/3/5 Jeesoo Shin <bsheep@gmail.com>
> Thank you for reply. :)
> Yes I did multiple thread.
> 160, 320 gave me same result.
> 
> On 3/5/12, ruslan usifov <ruslan.usifov@gmail.com> wrote:
> > 2012/3/5 Jeesoo Shin <bsheep@gmail.com>
> >
> >> Hi all.
> >>
> >> I have very SLOW READ here. :-(
> >> I made a cluster with three node (aws xlarge, replication = 3)
> >> Cassandra version is 1.0.6
> >> I have inserted 1,000,000 rows. (standard column)
> >> Each row has 200 columns.
> >> Each column has 16 byte key,  512 byte value.
> >>
> >> I used Hector createSliceQuery to get one column in a row.
> >> This basic query(random row, fixed column) is created with multiple
> >> thread and hit cassandra.
> >>
> >> I only get up to 140 request per second. Is this all I can get for read?
> >> Or am I doing something wrong?
> >> Interestingly, when I request rows which doesn't exist, it goes up to
> >> 1600 per second.
> >>
> >>
> > You must test read performance by paralel test (ie multiple threads). The
> > result when not existent rows are more faster is result of bloom filter
> >
> >
> >
> >>
> >> ANY insight, share will be extremely helpful.
> >> Thank you.
> >>
> >> Regards,
> >> Jeesoo.
> >>
> >
> 


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