From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id 4F4529000C1 for ; Wed, 27 Apr 2011 04:43:24 -0400 (EDT) Date: Wed, 27 Apr 2011 09:43:19 +0100 From: Mel Gorman Subject: Re: [PATCH 00/13] Swap-over-NBD without deadlocking Message-ID: <20110427084319.GM4658@suse.de> References: <1303803414-5937-1-git-send-email-mgorman@suse.de> <1303827785.20212.266.camel@twins> <20110426144635.GK4658@suse.de> <1303829449.20212.285.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <1303829449.20212.285.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 04:50:49PM +0200, Peter Zijlstra wrote: > On Tue, 2011-04-26 at 15:46 +0100, Mel Gorman wrote: > > > > 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. > > Right, so the thing I was worried about was a route-cache poison attack > where someone would spam the machine such that it would create a lot of > route cache entries and might flush the one we needed just as we needed > it. > > Pinning the one entry we need would solve that (if possible). That is a possibility all right, nice thoughts there. Ok, as I do not want this series to grow to the point where it is unreviewable, I'll mark pinning the routing cache entry for a follow-on series. In this series, the throttling logic should allow a new routing cache entry to be allocated by kswapd as it's immune to the throttle. Thanks. -- 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