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From:Greg Whalin Date:May 7 2005 2:01am
Subject:Re: MySQL not using optimum disk throughput.
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What drives are you using?  For SCSI RAID, you definitly want deadline 
scheduler.  That said, even after the switch to deadline, we saw our 
Opteron's running way slow (compared to older slower Xeons).  Whatever 
the problem is, we fought it for quite a while (though difficult to test 
too much w/ production dbs) and ended up rolling back to 2.4.

Kevin Burton wrote:
> Kevin Burton wrote:
> 
>> Greg Whalin wrote:
>>
>>>
>>> Deadline was much faster.  Using sysbench:
>>>
>>> test:
>>> sysbench --num-threads=16 --test=fileio --file-total-size=20G 
>>> --file-test-mode=rndrw run
>>
>>
>>
> So... FYI.  I rebooted with elevator=deadline as a kernel param.
> 
> db2:~# cat /sys/block/sda/queue/scheduler
> noop anticipatory [deadline] cfq
> 
> (which I assume means I'm now running deadline.  Is there any other way 
> to find out?)
> 
> And no performance diff.  Note that you're benchmarks only show a 20M 
> addition overhead.  We're about 60x too slow for these drives so I'm not 
> sure what could be going on here :-/
> 
> Kevin
> 

Thread
MySQL not using optimum disk throughput.Kevin Burton6 May
  • Re: MySQL not using optimum disk throughput.Dan Nelson7 May
RE: MySQL not using optimum disk throughput.Dathan Pattishall7 May
  • Re: MySQL not using optimum disk throughput.Greg Whalin7 May
    • Re: MySQL not using optimum disk throughput.Kevin Burton7 May
      • Re: MySQL not using optimum disk throughput.Greg Whalin7 May
        • Re: MySQL not using optimum disk throughput.Kevin Burton7 May
          • Re: MySQL not using optimum disk throughput.Kevin Burton7 May
            • Re: MySQL not using optimum disk throughput.Greg Whalin7 May
              • Re: MySQL not using optimum disk throughput.Kevin Burton7 May
                • Re: MySQL not using optimum disk throughput.Atle Veka7 May
                  • Re: MySQL not using optimum disk throughput.Kevin Burton7 May
                    • Re: MySQL not using optimum disk throughput.Atle Veka7 May
                  • Re: MySQL not using optimum disk throughput.Dan Nelson8 May
              • Re: MySQL not using optimum disk throughput.Peter Zaitsev7 May
                • Re: MySQL not using optimum disk throughput.Greg Whalin7 May
                  • Re: MySQL not using optimum disk throughput.Peter Zaitsev1 Jun
                    • RE: MySQL not using optimum disk throughput.Richard Dale1 Jun
        • Re: MySQL not using optimum disk throughput.Kevin Burton9 May
          • Re: MySQL not using optimum disk throughput.Greg Whalin9 May
            • Re: MySQL not using optimum disk throughput.Kevin Burton9 May
              • Re: MySQL not using optimum disk throughput.Greg Whalin9 May
                • Re: MySQL not using optimum disk throughput.Kevin Burton9 May
Re: MySQL not using optimum disk throughput.John David Duncan7 May
  • Re: MySQL not using optimum disk throughput.Peter Zaitsev7 May