Re: [git patches] IDE update

From: Grant Coady
Date: Thu Jul 07 2005 - 19:08:51 EST


On Thu, 07 Jul 2005 18:32:52 -0400, Mark Lord <liml@xxxxxx> wrote:
>
>hdparm can also use O_DIRECT for the -t timing test.

I've not been able to get dual channel I/O speed faster than single
interface speed, either as 'md' RAID0 or simultaneous reading or
writing done the other day:

Time to write or read 500MB file:

>summary 2.4.31-hf1 2.6.12.2
>boxen \ time -> w r w r
>--------------- ---- ---- ---- ----
...
>peetoo 33 20 26.5 22
>(simultaneuous 57 37.5 52 38.5)

MB/s 2.4.31-hf1 2.6.12.2
w r w r
single 15 25 19 23
dual 17.5 27 19 26

These timings show very little happening in parallel, is that normal?

Thanks,
--Grant.

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