From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [PATCH 0/3] Use one zonelist per node instead of multiple zonelists v2 From: Lee Schermerhorn In-Reply-To: <20070808214420.GD2441@skynet.ie> References: <20070808161504.32320.79576.sendpatchset@skynet.skynet.ie> <1186597819.5055.37.camel@localhost> <20070808214420.GD2441@skynet.ie> Content-Type: text/plain Date: Wed, 08 Aug 2007 18:40:07 -0400 Message-Id: <1186612807.5055.106.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Mel Gorman Cc: Christoph Lameter , pj@sgi.com, ak@suse.de, kamezawa.hiroyu@jp.fujitsu.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Wed, 2007-08-08 at 22:44 +0100, Mel Gorman wrote: > On (08/08/07 14:30), Lee Schermerhorn didst pronounce: > > On Wed, 2007-08-08 at 10:36 -0700, Christoph Lameter wrote: > > > On Wed, 8 Aug 2007, Mel Gorman wrote: > > > > > > > o Remove bind_zonelist() (Patch in progress, very messy right now) > > > > > > Will this also allow us to avoid always hitting the first node of an > > > MPOL_BIND first? > > > > An idea: > > > > Apologies if someone already suggested this and I missed it. Too much > > traffic... > > > > instead of passing a zonelist for BIND policy, how about passing [to > > __alloc_pages(), I think] a starting node, a nodemask, and gfp flags for > > zone and modifiers. > > Yes, this has come up before although it wasn't my initial suggestion. I > thought maybe it was yours but I'm not sure anymore. I'm working through > it at the moment. I've heard/seen Christoph mention passing a nodemask to alloc_pages a few times, but hadn't seen any of the details. Got me thinking.. > With the patch currently, a a nodemask is passed in for > filtering which should be enough as the zonelist being used should be enough > information to indicate the starting node. It'll take me a while to absorb the patch, so I'll just ask: Where does the zonelist for the argument come from? If the the bind policy zonelist is removed, then does it come from a node? There'll be only one per node with your other patches, right? So you had to have a node id, to look up the zonelist? Do you need the zonelist elsewhere, outside of alloc_pages()? If not, why not just let alloc_pages look it up from a starting node [which I think can be determined from the policy]? OK, that's a lot of questions. no need to answer. That's just what I'm thinking re: all this. I'll wait and see how the patch develops. > > The signature of __alloc_pages() becomes > > static page * fastcall > __alloc_pages_nodemask(gfp_t gfp_mask, nodemask_t *nodemask, > unsigned int order, struct zonelist *zonelist) > > > For various policies, the arguments would look like this: > > Policy start node nodemask > > > > default local node cpuset_current_mems_allowed > > > > preferred preferred_node cpuset_current_mems_allowed > > > > interleave computed node cpuset_current_mems_allowed > > > > bind local node policy nodemask [replaces bind > > zonelist in mempolicy] > > > > The last one is the most interesting. Much of the patch in development > involves deleting the custom node stuff. I've included the patch below if > you're curious. I wanted to get one-zonelist out first to see if we could > agree on that before going further with it. Again, it'll be a while. Thanks, Lee -- 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/ . Don't email: email@kvack.org