From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 29 Aug 2002 16:35:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 29 Aug 2002 16:35:42 -0400 Received: from svr-ganmtc-appserv-mgmt.ncf.coxexpress.com ([24.136.46.5]:12807 "EHLO svr-ganmtc-appserv-mgmt.ncf.coxexpress.com") by vger.kernel.org with ESMTP id ; Thu, 29 Aug 2002 16:35:38 -0400 Subject: Re: [PATCH] low-latency zap_page_range() From: Robert Love To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org In-Reply-To: <3D6E844C.4E756D10@zip.com.au> References: <1030635100.939.2551.camel@phantasy> <3D6E844C.4E756D10@zip.com.au> Content-Type: text/plain Content-Transfer-Encoding: 7bit X-Mailer: Ximian Evolution 1.0.8 Date: 29 Aug 2002 16:40:02 -0400 Message-Id: <1030653602.939.2677.camel@phantasy> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2002-08-29 at 16:30, Andrew Morton wrote: > However with your change, we'll only ever put 256 pages into the > mmu_gather_t. Half of that thing's buffer is unused and the > invalidation rate will be doubled during teardown of large > address ranges. Agreed. Go for it. Hm, unless, since 507 vs 256 is not the end of the world and latency is already low, we want to just make it always (FREE_PTE_NR*PAGE_SIZE)... As long as the "cond_resched_lock()" is a preempt only thing, I also agree with making ZAP_BLOCK_SIZE ~0 on !CONFIG_PREEMPT - unless we wanted to unconditionally drop the locks and let preempt just do the right thing and also reduce SMP lock contention in the SMP case. Robert Love From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [PATCH] low-latency zap_page_range() From: Robert Love In-Reply-To: <3D6E844C.4E756D10@zip.com.au> References: <1030635100.939.2551.camel@phantasy> <3D6E844C.4E756D10@zip.com.au> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: 29 Aug 2002 16:40:02 -0400 Message-Id: <1030653602.939.2677.camel@phantasy> Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Thu, 2002-08-29 at 16:30, Andrew Morton wrote: > However with your change, we'll only ever put 256 pages into the > mmu_gather_t. Half of that thing's buffer is unused and the > invalidation rate will be doubled during teardown of large > address ranges. Agreed. Go for it. Hm, unless, since 507 vs 256 is not the end of the world and latency is already low, we want to just make it always (FREE_PTE_NR*PAGE_SIZE)... As long as the "cond_resched_lock()" is a preempt only thing, I also agree with making ZAP_BLOCK_SIZE ~0 on !CONFIG_PREEMPT - unless we wanted to unconditionally drop the locks and let preempt just do the right thing and also reduce SMP lock contention in the SMP case. Robert Love -- 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/