From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with SMTP id 81C769000C1 for ; Tue, 26 Apr 2011 10:46:40 -0400 (EDT) Date: Tue, 26 Apr 2011 15:46:35 +0100 From: Mel Gorman Subject: Re: [PATCH 00/13] Swap-over-NBD without deadlocking Message-ID: <20110426144635.GK4658@suse.de> References: <1303803414-5937-1-git-send-email-mgorman@suse.de> <1303827785.20212.266.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <1303827785.20212.266.camel@twins> Sender: owner-linux-mm@kvack.org List-ID: To: Peter Zijlstra Cc: Linux-MM , Linux-Netdev , LKML , David Miller , Neil Brown On Tue, Apr 26, 2011 at 04:23:05PM +0200, Peter Zijlstra wrote: > On Tue, 2011-04-26 at 08:36 +0100, Mel Gorman wrote: > > Comments? > > Last time I brought up the whole swap over network bits I was pointed > towards the generic skb recycling work: > > http://lwn.net/Articles/332037/ > > as a means to pre-allocate memory, I'd taken note of this to take a much closer look if it turned out reservations were necessary and to find out what happened with these patches. So far, bigger reservations have *not* been required but I agree recycling SKBs may be a better alternative than large reservations or preallocations if they are necessary. > and it was suggested to simply pin > the few route-cache entries required to route these packets and > dis-allow swap packets to be fragmented (these last two avoid lots of > funny allocation cases in the network stack). > I did find that only a few route-cache entries should be required. In the original patches I worked with, there was a reservation for the maximum possible number of route-cache entries. I thought this was overkill and instead reserved 1-per-active-swapfile-backed-by-NFS. -- Mel Gorman SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org