From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753355Ab1HWGsc (ORCPT ); Tue, 23 Aug 2011 02:48:32 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:19416 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751777Ab1HWGsa (ORCPT ); Tue, 23 Aug 2011 02:48:30 -0400 Message-ID: <4E534D13.5020102@openvz.org> Date: Tue, 23 Aug 2011 10:47:47 +0400 From: Konstantin Khlebnikov User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.19) Gecko/20110702 Iceape/2.0.14 MIME-Version: 1.0 To: Andrew Morton CC: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Dave Chinner Subject: Re: [PATCH 1/2] vmscan: fix initial shrinker size handling References: <20110822101721.19462.63082.stgit@zurg> <20110822143006.60f4b560.akpm@linux-foundation.org> In-Reply-To: <20110822143006.60f4b560.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Andrew Morton wrote: >> long new_nr; >> long batch_size = shrinker->batch ? shrinker->batch >> : SHRINK_BATCH; >> >> + max_pass = do_shrinker_shrink(shrinker, shrink, 0); >> + if (max_pass<= 0) >> + continue; >> + >> /* >> * copy the current shrinker scan count into a local variable >> * and zero it so that other concurrent shrinker invocations >> @@ -266,7 +270,6 @@ unsigned long shrink_slab(struct shrink_control *shrink, >> } while (cmpxchg(&shrinker->nr, nr, 0) != nr); >> >> total_scan = nr; >> - max_pass = do_shrinker_shrink(shrinker, shrink, 0); >> delta = (4 * nr_pages_scanned) / shrinker->seeks; >> delta *= max_pass; >> do_div(delta, lru_pages + 1); > > Why was the shrinker call moved to before the alteration of shrinker->nr? I think, if we skip shrinker we shouldn't reset accumulated pressure, because next reclaimer (for example with less strict gfp) can use it.