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Re: MySQL Performance Woody Vs Sarge



Simon:
> 
> The only difference i can find is that an htparm on the RAID drive:
> 
> woody:
> 
> Timing buffer-cache reads:   128 MB in  0.46 seconds =278.26 MB/sec
> Timing buffered disk reads:  64 MB in  1.33 seconds = 48.12 MB/sec
> 
> sarge:
> 
> Timing cached reads:   196 MB in  3.38 seconds =  57.98 MB/sec
> Timing buffered disk reads:  130 MB in  3.01 seconds =  43.22 MB/sec
> 
> Seems to directly relate to the issue? I dont know.

It looks like that. But the big difference here doesn't lie in the hard
drive, but in memory and/or CPU. From the hdparm manpage:

-T  [...] This displays the speed of reading directly from the Linux
    buffer cache without disk access.  This measurement is essentially
    an indication of  the throughput  of the processor, cache, and
    memory of the system under test.

So you better check for correct settings of clock speed and the like.
Look for differences in BIOS settings and check your RAM.

J.
-- 
I spend money without thinking on products and clothes that I believe
will enhance my social standing.
[Agree]   [Disagree]
                 <http://www.slowlydownward.com/NODATA/data_enter2.html>

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