From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f199.google.com (mail-io0-f199.google.com [209.85.223.199]) by kanga.kvack.org (Postfix) with ESMTP id 1071C6B0069 for ; Sat, 7 Jan 2017 13:37:43 -0500 (EST) Received: by mail-io0-f199.google.com with SMTP id c80so26933581iod.4 for ; Sat, 07 Jan 2017 10:37:43 -0800 (PST) Received: from mail-io0-x234.google.com (mail-io0-x234.google.com. [2607:f8b0:4001:c06::234]) by mx.google.com with ESMTPS id m94si3420430iod.161.2017.01.07.10.37.42 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 07 Jan 2017 10:37:42 -0800 (PST) Received: by mail-io0-x234.google.com with SMTP id j13so315340iod.3 for ; Sat, 07 Jan 2017 10:37:42 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20170107092746.GC5047@dhcp22.suse.cz> References: <20170106095115.GG5556@dhcp22.suse.cz> <20170106100433.GH5556@dhcp22.suse.cz> <20170106121642.GJ5556@dhcp22.suse.cz> <1483740889.9712.44.camel@edumazet-glaptop3.roam.corp.google.com> <20170107092746.GC5047@dhcp22.suse.cz> From: Eric Dumazet Date: Sat, 7 Jan 2017 10:37:41 -0800 Message-ID: Subject: Re: weird allocation pattern in alloc_ila_locks Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Eric Dumazet , Tom Herbert , linux-mm@kvack.org, LKML On Sat, Jan 7, 2017 at 1:27 AM, Michal Hocko wrote: > On Fri 06-01-17 14:14:49, Eric Dumazet wrote: >> I believe the intent was to get NUMA spreading, a bit like what we have >> in alloc_large_system_hash() when hashdist == HASHDIST_DEFAULT > > Hmm, I am not sure this works as expected then. Because it is more > likely that all pages backing the vmallocked area will come from the > local node than spread around more nodes. Or did I miss your point? Well, you missed that vmalloc() is aware of NUMA policies. If current process has requested interleave on 2 nodes (as it is done at boot time on a dual node system), then vmalloc() of 8 pages will allocate 4 pages on each node. If you force/attempt a kmalloc() of one order-3 page, chances are very high to get all memory on one single node. -- 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