Very low disk performance on 5.x

[Petri Helenius]

Poul-Henning Kamp wrote:

>In message <427626DC.5030702 at centtech.com>, Eric Anderson writes:
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>>Don't mean to be terse here, but I'm talking about the same test done an 
>>two different RAID5 configurations, with different disks, and not just 
>>me - other users in this very thread see the same issue..
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>Uhm, if you are using RAID5 and your requests are not aligned and
>sized after the RAID5 you should *expect* read performance to be poor.
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>If you your request ends up accessing two different blocks even just
>once per stripe, this totally kills performance.
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My tests were using RAID10 and just striping. (RAID0 might be the right 
name for it)

Pete