From mboxrd@z Thu Jan  1 00:00:00 1970
From: Max Waterman <davidmaxwaterman+gmane@fastmail.co.uk>
Subject: Re: md faster than h/w?
Date: Mon, 16 Jan 2006 13:33:39 +0800
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Max Waterman wrote:
>
> Then I unmount /dev/sdb and it's back up to 155MB/s !?!?!
> 
> It's not making any sense to me :(
> 

OK, the 'hdparm -t' numbers are always low for a device that is mounted.

i.e. an unmounted device gets 3-4 times the bandwidth of a mounted device.

Of course, bonnie++ only works on mounted devices, but gives me
reasonable (but not great) numbers (130MB/s) which don't seem to vary
too much with the kernel version.

Max.