From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from zps38.corp.google.com (zps38.corp.google.com [172.25.146.38]) by smtp-out.google.com with ESMTP id l6DL9r3J029350 for ; Fri, 13 Jul 2007 14:09:53 -0700 Received: from an-out-0708.google.com (ancc31.prod.google.com [10.100.29.31]) by zps38.corp.google.com with ESMTP id l6DL9iiX009070 for ; Fri, 13 Jul 2007 14:09:45 -0700 Received: by an-out-0708.google.com with SMTP id c31so138719anc for ; Fri, 13 Jul 2007 14:09:44 -0700 (PDT) Message-ID: Date: Fri, 13 Jul 2007 14:09:44 -0700 From: "Ken Chen" Subject: Re: [PATCH 5/5] [hugetlb] Try to grow pool for MAP_SHARED mappings In-Reply-To: <20070713130508.6f5b9bbb.pj@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20070713151621.17750.58171.stgit@kernel> <20070713151717.17750.44865.stgit@kernel> <20070713130508.6f5b9bbb.pj@sgi.com> Sender: owner-linux-mm@kvack.org Return-Path: To: Paul Jackson Cc: Adam Litke , linux-mm@kvack.org, mel@skynet.ie, apw@shadowen.org, wli@holomorphy.com, clameter@sgi.com List-ID: On 7/13/07, Paul Jackson wrote: > But the cpuset behaviour of this hugetlb stuff looks suspicious to me: > 1) The code in alloc_fresh_huge_page() seems to round robin over > the entire system, spreading the hugetlb pages uniformly on all nodes. > If one a task in one small cpuset starts aggressively allocating hugetlb > pages, do you think this will work, alloc_fresh_huge_page() is used to fill up the hugetlb page pool. It is called through sysctl path. The path that dish out page out of the pool and allocate to task is alloc_huge_page(), which should obey both mempolicy and cpuset constrain. > 2) I don't see what keeps us from picking hugetlb pages off -any- node in the > system, perhaps way outside the current cpuset. I think it is checked in dequeue_huge_page(): if (cpuset_zone_allowed_softwall(*z, GFP_HIGHUSER) && !list_empty(&hugepage_freelists[nid])) break; -- 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