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From Arijit Mukherjee <ariji...@gmail.com>
Subject Re: client threads locked up - JIRA ISSUE 1594
Date Wed, 26 Jan 2011 11:57:59 GMT
I'm using the jars packed in Hector 0.6.0-19 (the one compatible with
Cassandra 0.6.*). I wanted to use hector, but for some reason I
haven't been able to do so yet. What I'm doing is a POC kind of thing,
and only if it works out properly, we'll go on to build on it.

The reason I asked this question in the first place was a high idle
cpu percentage. I'm currently doing the POC on an 8-core machine. I
have 8 client threads inserting data into Cassandra. But, most of the
time, I can see 40-45% user time, 15-20% system time and the rest idle
- for each core, even if I change the number of client threads
(increase or decrease). Then I used jstack on my Java application, and
the result was exactly similar to the JIRA issue 1594.

I was just wondering whether this can be the reason for idle CPU.
Because the same application was earlier tried with Lucene (to store
the indices) and we had about 90% CPU utilization. We've replaced
Lucene with Cassandra (to store the index and inverted index), and the
CPU utillization is down, the total time required went up by 5 folds
(for the same data set). We tried Cassandra directly as apparently
Lucandra is 10% slower than Cassandra...

Arijit

On 25 January 2011 20:30, Nate McCall <nate@riptano.com> wrote:
> What version of the Thrift API are you using?
>
> (In general, you should use an existing client library rather than
> rolling your own - I recommend Hector:
> https://github.com/rantav/hector).
>
> On Tue, Jan 25, 2011 at 12:38 AM, Arijit Mukherjee <arijit72@gmail.com> wrote:
>> I'm using Cassandra 0.6.8. I'm not using Hector - it's just raw thrift APIs.
>>
>> Arijit
>>
>> On 21 January 2011 22:13, Nate McCall <nate@riptano.com> wrote:
>>> What versions of Cassandra and Hector? The versions mentioned on this
>>> ticket are both several releases behind.
>>>
>>> On Fri, Jan 21, 2011 at 3:53 AM, Arijit Mukherjee <arijit72@gmail.com>
wrote:
>>>> Hi All
>>>>
>>>> I'm facing the same issue as this one mentioned here -
>>>> https://issues.apache.org/jira/browse/CASSANDRA-1594
>>>>
>>>> Is there any solution or work-around for this?
>>>>
>>>> Regards
>>>> Arijit
>>>>
>>>>
>>>> --
>>>> "And when the night is cloudy,
>>>> There is still a light that shines on me,
>>>> Shine on until tomorrow, let it be."
>>>>
>>>
>>
>>
>>
>> --
>> "And when the night is cloudy,
>> There is still a light that shines on me,
>> Shine on until tomorrow, let it be."
>>
>



-- 
"And when the night is cloudy,
There is still a light that shines on me,
Shine on until tomorrow, let it be."

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