From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38646) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fBIrB-0000na-8w for qemu-devel@nongnu.org; Wed, 25 Apr 2018 07:45:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fBIrA-0002BV-9B for qemu-devel@nongnu.org; Wed, 25 Apr 2018 07:45:05 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:32974 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 1fBIrA-0002Ag-4E for qemu-devel@nongnu.org; Wed, 25 Apr 2018 07:45:04 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9A423406EA4F for ; Wed, 25 Apr 2018 11:45:00 +0000 (UTC) From: Juan Quintela In-Reply-To: <20180425112723.1111-1-quintela@redhat.com> (Juan Quintela's message of "Wed, 25 Apr 2018 13:27:02 +0200") References: <20180425112723.1111-1-quintela@redhat.com> Reply-To: quintela@redhat.com Date: Wed, 25 Apr 2018 13:44:51 +0200 Message-ID: <87sh7jy0gc.fsf@secure.mitica> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [PATCH v12 00/21] Multifd List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: dgilbert@redhat.com, lvivier@redhat.com, peterx@redhat.com Juan Quintela wrote: > Hi > > > [v12] > > Big news, it is not RFC anymore, it works reliabely for me. > > Changes: > - Locknig changed completely (several times) > - We now send all pages through the channels. In a 2GB guest with 1 disk and a network card, the amount of data send for RAM was 80KB. > - This is not optimized yet, but it shouws clear improvements over precopy. testing over localhost networking I can guet: > - 2 VCPUs guest > - 2GB RAM > - runn stress --vm 4 --vm 500GB (i.e. dirtying 2GB or RAM each second) > > - Total time: precopy ~50seconds, multifd around 11seconds > - Bandwidth usage is around 273MB/s vs 71MB/s on the same hardware > > This is very preleminary testing, will send more numbers when I got them. But looks promissing. > > Things that will be improved later: > - Initial synchronization is too slow (around 1s) > - We synchronize all threads after each RAM section, we can move to only > synchronize them after we have done a bitmap syncrhronization > - We can improve bitmap walking (but that is independent of multifd) I forgot to put there that on the last 4 patches, I have not been able to split them in a way that: - is logical for review - works for multifd tests in all versions So, I ended trynig to get the "logical" viewe, and it works after the last patch. Why is that? - Before I am able to transmit data, I need to be able to end/synchronize the different channels - To finish channels in case of error, I just close the channels But I can't opet then yet. I have to think if I can come with a simpler way to split it, but you can also consider that the last 3-4 patches are a single one. Later, Juan.