From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37129) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fnFVe-0006uY-52 for qemu-devel@nongnu.org; Tue, 07 Aug 2018 23:51:43 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fnFVa-00027b-7C for qemu-devel@nongnu.org; Tue, 07 Aug 2018 23:51:42 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:55106 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fnFVa-00027M-1k for qemu-devel@nongnu.org; Tue, 07 Aug 2018 23:51:38 -0400 Date: Wed, 8 Aug 2018 11:51:27 +0800 From: Peter Xu Message-ID: <20180808035127.GD24415@xz-mi> References: <20180807091209.13531-1-xiaoguangrong@tencent.com> <20180807091209.13531-2-xiaoguangrong@tencent.com> <6fb46b1e-5cae-24ec-acd6-72ba562a5c05@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <6fb46b1e-5cae-24ec-acd6-72ba562a5c05@redhat.com> Subject: Re: [Qemu-devel] [PATCH v3 01/10] migration: do not wait for free thread List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake Cc: guangrong.xiao@gmail.com, pbonzini@redhat.com, mst@redhat.com, mtosatti@redhat.com, qemu-devel@nongnu.org, kvm@vger.kernel.org, dgilbert@redhat.com, wei.w.wang@intel.com, jiang.biao2@zte.com.cn, Xiao Guangrong On Tue, Aug 07, 2018 at 08:29:54AM -0500, Eric Blake wrote: > On 08/07/2018 04:12 AM, guangrong.xiao@gmail.com wrote: > > From: Xiao Guangrong > > > > Instead of putting the main thread to sleep state to wait for > > free compression thread, we can directly post it out as normal > > page that reduces the latency and uses CPUs more efficiently > > > > A parameter, compress-wait-thread, is introduced, it can be > > enabled if the user really wants the old behavior > > > > Signed-off-by: Xiao Guangrong > > --- > > > +++ b/qapi/migration.json > > @@ -462,6 +462,11 @@ > > # @compress-threads: Set compression thread count to be used in live migration, > > # the compression thread count is an integer between 1 and 255. > > # > > +# @compress-wait-thread: Wait if no thread is free to compress the memory page > > +# if it's enabled, otherwise, the page will be posted out immediately > > +# in the main thread without compression. It's true on default. > > +# (Since: 3.1) > > Grammar suggestion: > > @compress-wait-thread: Controls behavior when all compression threads are > currently busy. If true (default), wait for a free compression thread to > become available; otherwise, send the page uncompressed. (Since 3.1) Eric's version seems better. With that: Reviewed-by: Peter Xu Regards, -- Peter Xu