Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755670Ab3D0LYZ (ORCPT ); Sat, 27 Apr 2013 07:24:25 -0400 Received: from e39.co.us.ibm.com ([32.97.110.160]:60496 "EHLO e39.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751712Ab3D0LYY (ORCPT ); Sat, 27 Apr 2013 07:24:24 -0400 Date: Sat, 27 Apr 2013 19:24:18 +0800 From: Han Pingtian To: Christoph Lameter Cc: LKML , mhocko@suse.cz, penberg@kernel.org, rientjes@google.com, linux-mm@kvack.org Subject: Re: OOM-killer and strange RSS value in 3.9-rc7 Message-ID: <20130427112418.GC4441@localhost.localdomain> Mail-Followup-To: Christoph Lameter , LKML , mhocko@suse.cz, penberg@kernel.org, rientjes@google.com, linux-mm@kvack.org References: <20130418101541.GC2672@localhost.localdomain> <20130418175513.GA12581@dhcp22.suse.cz> <20130423131558.GH8001@dhcp22.suse.cz> <20130424044848.GI2672@localhost.localdomain> <20130424094732.GB31960@dhcp22.suse.cz> <0000013e3cb0340d-00f360e3-076b-478e-b94c-ddd4476196ce-000000@email.amazonses.com> <20130425060705.GK2672@localhost.localdomain> <0000013e427023d7-9456c313-8654-420c-b85a-cb79cc3c4ffc-000000@email.amazonses.com> <20130426062436.GB4441@localhost.localdomain> <0000013e46cba821-d5c54c99-3b5c-4669-9a54-9fb8f4ee516f-000000@email.amazonses.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0000013e46cba821-d5c54c99-3b5c-4669-9a54-9fb8f4ee516f-000000@email.amazonses.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13042711-3620-0000-0000-00000237D9BA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3108 Lines: 57 On Fri, Apr 26, 2013 at 02:42:32PM +0000, Christoph Lameter wrote: > On Fri, 26 Apr 2013, Han Pingtian wrote: > > > Could you give me some hints about how to verify them? Only I can do is > > adding two printk() statements to print the vaules in those two > > functions: > > Ok thats good. nr->partial needs to be bigger than min_partial in order > for frees to occur. So they do occur. > > > And looks like only printk() in __slab_free() is invoked. I got about 6764 > > lines of something like this: > > > > -------------------------------------------------------------------------------- > > Apr 26 01:04:05 riblp3 kernel: [ 6.969775] In __slab_free(); kmalloc-8192: n->nr_partial=2, s->min_partial=6 > > Apr 26 01:04:05 riblp3 kernel: [ 6.970154] In __slab_free(); kmalloc-8192: n->nr_partial=3, s->min_partial=6 > > Apr 26 01:04:05 riblp3 kernel: [ 6.979489] In __slab_free(); kmalloc-8192: n->nr_partial=4, s->min_partial=6 > > Apr 26 01:04:05 riblp3 kernel: [ 6.979823] In __slab_free(); kmalloc-8192: n->nr_partial=5, s->min_partial=6 > > Apr 26 01:04:05 riblp3 kernel: [ 9.500383] In __slab_free(); kmalloc-8192: n->nr_partial=7, s->min_partial=6 > > Apr 26 01:04:05 riblp3 kernel: [ 9.509736] In __slab_free(); kmalloc-8192: n->nr_partial=7, s->min_partial=6 > > Apr 26 01:04:08 riblp3 kernel: [ 42.314395] In __slab_free(); kmalloc-8192: n->nr_partial=100, s->min_partial=6 > > Apr 26 01:04:08 riblp3 kernel: [ 42.410333] In __slab_free(); kmalloc-8192: n->nr_partial=100, s->min_partial=6 > > Apr 26 01:04:09 riblp3 kernel: [ 43.411851] In __slab_free(); kmalloc-8192: n->nr_partial=339, s->min_partial=6 > > Apr 26 01:04:09 riblp3 kernel: [ 43.411980] In __slab_free(); kmalloc-8192: n->nr_partial=338, s->min_partial=6 > > Apr 26 01:04:09 riblp3 kernel: [ 43.412083] In __slab_free(); kmalloc-8192: n->nr_partial=337, s->min_partial=6 > > -------------------------------------------------------------------------------- > > The s->min_partial is always "6" and most of n->nr_partial is bigger than > > its partner of the same line. > > Thats the way it should be. But the mystery is still there. Why do the > pages not get freed? Can you add a printk in __free_slab to verify that it > actually gets called? Print s->name to see which slab is affected by the > free. > I added a printk() like this: @@ -1388,6 +1388,8 @@ static void __free_slab(struct kmem_cache *s, struct page *page) int order = compound_order(page); int pages = 1 << order; + printk(KERN_INFO "__free_slab(): %s\n", s->name); + if (kmem_cache_debug(s)) { void *p; and it is called so many times that the boot cannot be finished. So maybe the memory isn't freed even though __free_slab() get called? > Is there any way I can run a powerpc kernel that shows the issue on x86 > with an emulator? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/