Re: High cpu usage after many inserts

On Wed, 2009-02-25 at 09:44 +0900, Jordan Tomkinson wrote:
>
>
> On Wed, Feb 25, 2009 at 9:23 AM, Joshua D. Drake
> <jd@commandprompt.com> wrote:
>
>
>         RAID5 outside of RAID 0 is the worst possible RAID level to
>         run with a
>         database. (of the commonly used raid level's that is).
>
>         It is very, very slow on random writes which is what databases
>         do.
>         Switch to RAID 10.
>
> surely being (real) hardware raid with 15k rpm disks this wouldn't be
> a huge issue unless a large amount of data was being written ?

Tests done by Mark Wong on a 3 disk 15k scsi versus 4 disk raid 10 scsi
show that RAID 10 is on average 30% faster.


Sincerely,

Joshua D. Drake

>
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