Re: RAID 0 not as fast as expected - Mailing list pgsql-performance

That's an all PCI-X box which makes sense.  There are 6 SATA controllers
in that little beastie also.  You can always count on Sun to provide
over engineered boxes.



> -----Original Message-----
> From: pgsql-performance-owner@postgresql.org
> [mailto:pgsql-performance-owner@postgresql.org] On Behalf Of
> Joshua D. Drake
> Sent: Friday, September 15, 2006 12:01 AM
> To: Luke Lonergan
> Cc: Craig A. James; pgsql-performance@postgresql.org
> Subject: Re: [PERFORM] RAID 0 not as fast as expected
>
> Luke Lonergan wrote:
> > Josh,
> >
> > On 9/14/06 8:47 PM, "Joshua D. Drake" <jd@commandprompt.com> wrote:
> >
> >>> I've obtained 1,950 MB/s using Linux software RAID on SATA drives.
> >> With what? :)
> >
> > Sun X4500 (aka Thumper) running stock RedHat 4.3 (actually
> CentOS 4.3)
> > with XFS and the linux md driver without lvm.  Here is a
> summary of the results:
> >
>
>
> Good god!
>
> >
> >  Read Test
> >  RAID Level Max Readahead (KB) RAID Chunksize Max Readahead
> on Disks
> > (KB) Max Time (s)  Read Bandwidth (MB/s)  0 65536 64 256 16.689
> > 1,917.43  0 4096 64 256 21.269  1,504.54  0 65536 256 256 17.967
> > 1,781.04  0 2816 256 256 18.835  1,698.96  0 65536 1024 256 18.538
> > 1,726.18  0 65536 64 512 18.295  1,749.11  0 65536 64 256 18.931
> > 1,690.35  0 65536 64 256 18.873  1,695.54  0 64768 64 256 18.545
> > 1,725.53  0 131172 64 256 18.548  1,725.25  0 131172 64
> 65536 19.046
> > 1,680.14  0 131172 64 524288 18.125  1,765.52  0 131172 64 1048576
> > 18.701  1,711.14
> >  5 2560 64 256 39.933  801.34
> >  5 16777216 64 256 37.76  847.46
> >  5 524288 64 256 53.497  598.16
> >  5 65536 32 256 38.472  831.77
> >  5 65536 32 256 38.004  842.02
> >  5 65536 32 256 37.884  844.68
> >  5 2560 16 256 41.39  773.13
> >  5 65536 16 256 48.902  654.37
> >  10 65536 64 256 83.256  384.36
> >  1+0 65536 64 256 19.394  1,649.99
> >  1+0 65536 64 256 19.047  1,680.05
> >  1+0 65536 64 256 19.195  1,667.10
> >  1+0 65536 64 256 18.806  1,701.58
> >  1+0 65536 64 256 18.848  1,697.79
> >  1+0 65536 64 256 18.371  1,741.88
> >  1+0 65536 64 256 21.446  1,492.12
> >  1+0 65536 64 256 20.254  1,579.93
> >
> >
>
>
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