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Date: Mon, 14 May 2007 09:29:15 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: Matt Mackall <mpm@selenic.com>
cc: Peter Zijlstra <a.p.zijlstra@chello.nl>, linux-kernel@vger.kernel.org,
       linux-mm@kvack.org, Thomas Graf <tgraf@suug.ch>,
       David Miller <davem@davemloft.net>,
       Andrew Morton <akpm@linux-foundation.org>,
       Daniel Phillips <phillips@google.com>,
       Pekka Enberg <penberg@cs.helsinki.fi>
Subject: Re: [PATCH 0/5] make slab gfp fair
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On Mon, 14 May 2007, Matt Mackall wrote:

> privileged thread                      unprivileged greedy process
> kmem_cache_alloc(...)
>    adds new slab page from lowmem pool

Yes but it returns an object for the privileged thread. Is that not 
enough?


> do_io()
>                                        kmem_cache_alloc(...)
>                                        kmem_cache_alloc(...)
>                                        kmem_cache_alloc(...)
>                                        kmem_cache_alloc(...)
>                                        kmem_cache_alloc(...)
>                                        ...
>                                           eats it all
> kmem_cache_alloc(...) -> ENOMEM
>    who ate my donuts?!
> 
> But I think this solution is somehow overkill. If we only care about
> this issue in the OOM avoidance case, then our rank reduces to a
> boolean.
> 
> -- 
> Mathematics is the supreme nostalgia of our time.
>