From mboxrd@z Thu Jan  1 00:00:00 1970
From: Justin Piszcz <jpiszcz@lucidpixels.com>
Subject: Re: major performance drop on raid5 due to context switches caused
 by small max_hw_sectors [partially resolved]
Date: Sun, 22 Apr 2007 11:53:03 -0400 (EDT)
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To: Pallai Roland <dap@mail.index.hu>
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On Sun, 22 Apr 2007, Pallai Roland wrote:

>
> On Sunday 22 April 2007 16:48:11 Justin Piszcz wrote:
>> Have you also optimized your stripe cache for writes?
> Not yet. Is it worth it?
>
>
> --
> d
>

Yes, it is-- well, if write speed is important to you that is?

Each of these write tests are averaged over three runs:

128k_stripe: 69.2MB/s
256k_stripe: 105.3MB/s
512k_stripe: 142.0MB/s
1024k_stripe: 144.6MB/s
2048k_stripe: 208.3MB/s
4096k_stripe: 223.6MB/s
8192k_stripe: 226.0MB/s
16384k_stripe: 215.0MB/s

What is your /sys/block/md[0-9]/md/stripe_cache_size?

Justin.