From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f200.google.com (mail-pf0-f200.google.com [209.85.192.200]) by kanga.kvack.org (Postfix) with ESMTP id 7F5CF6B038C for ; Thu, 16 Mar 2017 23:10:40 -0400 (EDT) Received: by mail-pf0-f200.google.com with SMTP id o126so116346352pfb.2 for ; Thu, 16 Mar 2017 20:10:40 -0700 (PDT) Received: from mga03.intel.com (mga03.intel.com. [134.134.136.65]) by mx.google.com with ESMTPS id e21si7163637pgi.84.2017.03.16.20.10.39 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 Mar 2017 20:10:39 -0700 (PDT) Date: Fri, 17 Mar 2017 11:10:48 +0800 From: Aaron Lu Subject: Re: [PATCH v2 0/5] mm: support parallel free of memory Message-ID: <20170317031048.GC18964@aaronlu.sh.intel.com> References: <1489568404-7817-1-git-send-email-aaron.lu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Vlastimil Babka Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Dave Hansen , Tim Chen , Andrew Morton , Ying Huang On Wed, Mar 15, 2017 at 03:56:02PM +0100, Vlastimil Babka wrote: > I wonder if the difference would be larger if the parallelism was done > on a higher level, something around unmap_page_range(). IIUC the current I guess I misunderstand you in my last email - doing it at unmap_page_range() level is essentially doing it at a per-VMA level since it is the main function used in unmap_single_vma(). We have tried that and felt that it's not flexible as the proposed approach since it wouldn't parallize well for: 1 work load that uses only 1 or very few huge VMA; 2 work load that has a lot of small VMAs. The code is nice and easy though(developed at v4.9 time frame):