From mboxrd@z Thu Jan  1 00:00:00 1970
From: Justin Piszcz <jpiszcz@lucidpixels.com>
Subject: Re: Time to  deprecate old RAID formats?
Date: Fri, 19 Oct 2007 12:45:39 -0400 (EDT)
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To: John Stoffel <john@stoffel.org>
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On Fri, 19 Oct 2007, John Stoffel wrote:

>>>>>> "Justin" == Justin Piszcz <jpiszcz@lucidpixels.com> writes:
>
> Justin> Is a bitmap created by default with 1.x?  I remember seeing
> Justin> reports of 15-30% performance degradation using a bitmap on a
> Justin> RAID5 with 1.x.
>
> Not according to the mdadm man page.  I'd probably give up that
> performance if it meant that re-syncing an array went much faster
> after a crash.
>
> I certainly use it on my RAID1 setup on my home machine.
>
> John
>

The performance AFTER a crash yes, but in general usage I remember seeing 
someone here doing benchmarks it had a negative affect on performance.

Justin.