Re: 2.5.59mm5 database 'benchmark' results

[Andrew Morton]

David Mansfield <[e-mail]> wrote:
>
> 
> Hi Nick, Andrew, lists,
> 
> I've been testing some recent kernels to see how they compare with a 
> particular database workload.  The workload is actually part of our 
> production process (last months run) but on a test server.  I'll describe 
> the platform and the workload, but first, the results :-)
> 
> kernel           minutes     comment
> -------------    ----------- ---------------------------------
> 2.4.20-aa1       134         i consider this 'baseline'
> 2.5.59           124         woo-hoo
> 2.4.18-19.7.xsmp 128         not bad for frankenstein's montster
> 2.5.59-mm5       157         uh-oh
> 
> Platform:
> HP LH3000 U3.  Dual 866 Mhz Intel Pentium III, 2GB ram.  megaraid 
> controller with two channels, each channel raid 5 PV on 6 15k scsi disks, 
> one megaraid LV per PV.
> 
> Two plain disks w/pairs of partitions in raid 1 for OS (redhat 7.3), a 
> second pair for Oracle redo-log (in a log 'group').
> 
> Oracle version 8.1.7 (no aio support in this release) is accessing
> datafiles on the two megaraid devices via /dev/raw stacked on top of
> device-mapper 

Rather impressed that you got all that to work ;)

It does appear that the IO scheduler change is not playing nicely with
software RAID.

> I'll test any kernel you throw my way.

Thanks.  Could you please try 2.5.59-mm5, with

http://www.zip.com.au/~akpm/linux/patches/2.5/2.5.59/2.5.59-mm5/broken-out/anticipatory_io_scheduling-2_5_59-mm3.patch

reverted?