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Date: Sun, 08 Oct 2006 15:02:06 -0600
From: Scott Long <scottl@samsco.org>
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To: Bruce Evans <bde@zeta.org.au>
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Cc: freebsd-fs@freebsd.org, Kris Kennaway <kris@obsecurity.org>
Subject: Re: 2 bonnies can stop disk activity permanently
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Bruce Evans wrote:

> On Sun, 8 Oct 2006, Scott Long wrote:
> 
>> Kris Kennaway wrote:
>>
>>> You forgot to even mention what version you're running ;-)
>>>
>>> Also show your kernel config file.  Configure DDB per the chapter on
> 
> 
>> No need for all of that information, the bug in vfs_bio.c is quite 
>> obvious. =-(  Fixing it will take some thought, though.
> 
> 
> Is it really obvious?  I think it is only obvious that many things are
> not quite right.  The quick fix of increasing BKVASIZE to the size of
> the largest buffer used should still work to prevent bkva fragmentation.
> 
> Bruce

The use of needsbuffer global presents a very wide open race.

Scott