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From: Neil Brown <neilb@cse.unsw.edu.au>
To: David Rees <dbr@greenhydrant.com>
Date: Thu, 30 Aug 2001 12:05:14 +1000 (EST)
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Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: kupdated, bdflush and kjournald stuck in D state on RAID1 device (deadlock?)
In-Reply-To: message from David Rees on Wednesday August 29
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On Wednesday August 29, dbr@greenhydrant.com wrote:
> 
> Now, when you say out-of-memory, do you mean out of memory plus swap?  Or
> just out of memory?

kmalloc(,GFP_NOIO) failure.  i.e. transient out-of-phyical-memory
condition. 
I suspect that kmalloc tends to fail only occasionally as the failure
will then to slow allocation requests down, and give the VM system a
bit of time to write more stuff out to disc and so free up memory.  
I am fairly sure that without the patch it will happen again, but
maybe not straight away.


NeilBrown

> 
> Running out of memory is quite common with the kernel always filling up
> buffers and cache, but running out of memory+swap is not common (and I know
> I didn't hit that in my setup!)
> 
> Thanks for your help,
> 
> -Dave