From: Mel Gorman <mgorman@suse.de>
To: Hillf Danton <dhillf@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Linux-MM <linux-mm@kvack.org>,
Linux-Netdev <netdev@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
David Miller <davem@davemloft.net>, Neil Brown <neilb@suse.de>,
Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH 00/15] Swap-over-NBD without deadlocking V8
Date: Wed, 8 Feb 2012 15:26:46 +0000 [thread overview]
Message-ID: <20120208152645.GK5938@suse.de> (raw)
In-Reply-To: <CAJd=RBDYMKRVSKVp3dAhTCtu_wNDyayCObVA7q6G=fbkKpmZUw@mail.gmail.com>
On Wed, Feb 08, 2012 at 08:51:11PM +0800, Hillf Danton wrote:
> On Tue, Feb 7, 2012 at 9:27 PM, Mel Gorman <mgorman@suse.de> wrote:
> > On Tue, Feb 07, 2012 at 08:45:18PM +0800, Hillf Danton wrote:
> >> If it is feasible to bypass hang by tuning min_mem_kbytes,
> >
> > No. Increasing or descreasing min_free_kbytes changes the timing but it
> > will still hang.
> >
> >> things may
> >> become simpler if NICs are also tagged.
> >
> > That would mean making changes to every driver and they do not necessarily
> > know what higher level protocol like TCP they are transmitting. How is
> > that simpler? What is the benefit?
> >
> The benefit is to avoid allocating sock buffer in softirq by recycling,
> then the changes in VM core maybe less.
>
The VM is responsible for swapping. It's reasonable that the core
VM has responsibility for it without trying to shove complexity into
drivers or elsewhere unnecessarily. I see some benefit in following on
by recycling some skbs and only allocating from softirq if no recycled
skbs are available. That potentially improves performance but I do not
recycling as a replacement.
--
Mel Gorman
SUSE Labs
prev parent reply other threads:[~2012-02-08 15:26 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-06 22:56 [PATCH 00/15] Swap-over-NBD without deadlocking V8 Mel Gorman
2012-02-06 22:56 ` [PATCH 01/15] mm: Serialize access to min_free_kbytes Mel Gorman
2012-02-08 18:47 ` Rik van Riel
2012-02-06 22:56 ` [PATCH 02/15] mm: sl[au]b: Add knowledge of PFMEMALLOC reserve pages Mel Gorman
2012-02-07 16:27 ` Christoph Lameter
2012-02-08 14:45 ` Mel Gorman
2012-02-08 15:14 ` Christoph Lameter
2012-02-08 16:34 ` Mel Gorman
2012-02-08 19:49 ` Christoph Lameter
2012-02-08 21:23 ` Mel Gorman
2012-02-08 22:13 ` Christoph Lameter
2012-02-09 12:50 ` Mel Gorman
2012-02-09 19:53 ` Christoph Lameter
2012-02-10 10:26 ` Mel Gorman
2012-02-10 21:01 ` Christoph Lameter
2012-02-10 22:07 ` Christoph Lameter
2012-02-13 10:12 ` Mel Gorman
2012-02-13 11:10 ` Mel Gorman
2012-02-06 22:56 ` [PATCH 03/15] mm: Introduce __GFP_MEMALLOC to allow access to emergency reserves Mel Gorman
2012-02-06 22:56 ` [PATCH 04/15] mm: allow PF_MEMALLOC from softirq context Mel Gorman
2012-02-06 22:56 ` [PATCH 05/15] mm: Ignore mempolicies when using ALLOC_NO_WATERMARK Mel Gorman
2012-02-06 22:56 ` [PATCH 06/15] net: Introduce sk_allocation() to allow addition of GFP flags depending on the individual socket Mel Gorman
2012-02-06 22:56 ` [PATCH 07/15] netvm: Allow the use of __GFP_MEMALLOC by specific sockets Mel Gorman
2012-02-06 22:56 ` [PATCH 08/15] netvm: Allow skb allocation to use PFMEMALLOC reserves Mel Gorman
2012-02-06 22:56 ` [PATCH 09/15] netvm: Propagate page->pfmemalloc to skb Mel Gorman
2012-02-06 22:56 ` [PATCH 10/15] netvm: Propagate page->pfmemalloc from netdev_alloc_page " Mel Gorman
2012-02-07 23:38 ` Alexander Duyck
2012-02-08 15:23 ` Mel Gorman
2012-02-06 22:56 ` [PATCH 11/15] netvm: Set PF_MEMALLOC as appropriate during SKB processing Mel Gorman
2012-02-06 22:56 ` [PATCH 12/15] mm: Micro-optimise slab to avoid a function call Mel Gorman
2012-02-06 22:56 ` [PATCH 13/15] nbd: Set SOCK_MEMALLOC for access to PFMEMALLOC reserves Mel Gorman
2012-02-06 22:56 ` [PATCH 14/15] mm: Throttle direct reclaimers if PF_MEMALLOC reserves are low and swap is backed by network storage Mel Gorman
2012-02-06 22:56 ` [PATCH 15/15] mm: Account for the number of times direct reclaimers get throttled Mel Gorman
2012-02-07 12:45 ` [PATCH 00/15] Swap-over-NBD without deadlocking V8 Hillf Danton
2012-02-07 13:27 ` Mel Gorman
2012-02-08 12:51 ` Hillf Danton
2012-02-08 15:26 ` Mel Gorman [this message]
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