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From Jake Luciani <jak...@gmail.com>
Subject Re: 0.7.2 slow memtables flushing
Date Sat, 19 Feb 2011 17:23:49 GMT
Are you running with JNA enabled? If so could you try disabling it?

On Sat, Feb 19, 2011 at 11:32 AM, Ivan Georgiev <yngwiie@bk.ru> wrote:

> On 19.2.2011 г. 16:43 ч., Jonathan Ellis wrote:
>
>> Flush code didn't change between 0.7.0 and 0.7.2. There must be some
>> other variable here. Memory pressure maybe?
>>
>
> Cloud you please elaborate on that one ?
> The conditions are exactly the same for the test with 0.7.0 and 0.7.2.
> By the way, 0.7.1 tests are similar to 0.7.2, while 0.7 early betas to
> 0.7.0 is fine.
>
> Ivan
>
>
> On 19.2.2011 г. 16:43 ч., Jonathan Ellis wrote:
>
>> Flush code didn't change between 0.7.0 and 0.7.2. There must be some
>> other variable here. Memory pressure maybe?
>>
>> On Sat, Feb 19, 2011 at 8:16 AM, Ivan Georgiev<yngwiie@bk.ru>  wrote:
>>
>>> Hi,
>>>
>>> I am testing 0.7.2 on a Windows 2003 x64 system(one node) and I am having
>>> the following problem.
>>> My insertion speed is relatively slow, so the memtables do not get full
>>> and
>>> the actual flushing is triggered by memtable_flush_after_mins, this
>>> happens
>>> on the hour mark. My problem with 0.7.2 is that when that happens, the
>>> cpu
>>> spikes to 25% overall usage (x4 Xeon) and the operation takes anywhere
>>> from
>>> 2 to 4 minutes, leaving the node not responding during that time. This
>>> has
>>> forced to me to increase the rpc timeout option to beyond what i feel
>>> comfortable with.
>>> I have run multiple tests with 0.7.0 and 0.7.2 with the same dataset and
>>> the
>>> results are consistent. During the same operation 0.7.0 takes about 10
>>> seconds to complete vs. 2 to 4 minutes for 0.7.2. I am attaching a log
>>> with
>>> the timestamps from one such flushing of 0.7.2. Please let me know if
>>> there
>>> is anything i can do to speed up and get results similar to 0.7.0.
>>>
>>> Regards:
>>> Ivan
>>>
>>> This is the log of the operations which took most time during the flush
>>> operation. Using 0.7.0, with the same number of operations the flushing
>>> takes less than 10 seconds.
>>>
>>> INFO 01:36:44,906 Enqueuing flush of
>>> Memtable-ArchiveFiles.6f776e65724944@1225856921(1619949 bytes, 34467
>>> operations)
>>> INFO 01:37:47,375 Completed flushing
>>> C:\Storage\data\Storage\ArchiveFiles.68617368-f-3-Data.db (5549187 bytes)
>>> INFO 01:37:47,375 Writing Memtable-ArchiveFiles.6e616d65@978152661
>>> (1619949
>>> bytes, 34467 operations)
>>> INFO 01:37:47,375 Enqueuing flush of
>>> Memtable-ArchiveFiles.706172656e74466f6c6465724944@2097700961(1619949
>>> bytes,
>>> 34467 operations)
>>> INFO 01:38:51,343 Completed flushing
>>> C:\Storage\data\Storage\ArchiveFiles.6e616d65-f-3-Data.db (3820265 bytes)
>>> INFO 01:38:51,343 Writing
>>> Memtable-ArchiveFiles.6f776e65724944@1225856921(1619949 bytes, 34467
>>> operations)
>>>
>>>
>>
>>
>


-- 
http://twitter.com/tjake

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