From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 99DB3C47094 for ; Mon, 7 Jun 2021 15:01:45 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0E95361057 for ; Mon, 7 Jun 2021 15:01:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0E95361057 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:35414 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lqGl5-00060k-Nk for qemu-devel@archiver.kernel.org; Mon, 07 Jun 2021 11:01:43 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35984) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lqGkH-0005JC-JO for qemu-devel@nongnu.org; Mon, 07 Jun 2021 11:00:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:53473) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lqGkA-0001LU-JY for qemu-devel@nongnu.org; Mon, 07 Jun 2021 11:00:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1623078045; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EkpjOsOas2F5drTotwrBlVtxcPSDBeL4KOmoFDgm7sA=; b=GcWtU3zL6rfflo3X00VifWjtFP3Al64y+tHvBG5A7I16zRdSmdWxG+rWxQal/8xPYJ+v4W inAZJK9d82pldMpP62tkJXWJ0gso3JHs+DSNlkAzbbj/ceX/HiZ+YwUzhNh5Adhji9XqeI CCGxpzURcoDNjslzs33chZmKb5uY8bQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-580--uQHRD3jMX2DSeR6xIACTg-1; Mon, 07 Jun 2021 11:00:38 -0400 X-MC-Unique: -uQHRD3jMX2DSeR6xIACTg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2A3C38030A0; Mon, 7 Jun 2021 15:00:37 +0000 (UTC) Received: from work-vm (ovpn-114-228.ams2.redhat.com [10.36.114.228]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 312015C1C2; Mon, 7 Jun 2021 15:00:30 +0000 (UTC) Date: Mon, 7 Jun 2021 16:00:28 +0100 From: "Dr. David Alan Gilbert" To: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= Subject: Re: [PATCH] migration/rdma: Use huge page register VM memory Message-ID: References: <51819991cecb42f6a619768bc61d0bfd@kingsoft.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/2.0.7 (2021-05-04) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.2, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: sunhao2 =?utf-8?B?W+WtmeaYil0=?= , YANGFENG1 =?utf-8?B?W+adqOWzsF0=?= , "quintela@redhat.com" , DENGLINWEN =?utf-8?B?W+mCk+ael+aWh10=?= , "qemu-devel@nongnu.org" , LIZHAOXIN1 =?utf-8?B?W+adjueFp+mRq10=?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Daniel P. Berrangé (berrange@redhat.com) wrote: > On Mon, Jun 07, 2021 at 01:57:02PM +0000, LIZHAOXIN1 [李照鑫] wrote: > > When using libvirt for RDMA live migration, if the VM memory is too large, > > it will take a lot of time to deregister the VM at the source side, resulting > > in a long downtime (VM 64G, deregister vm time is about 400ms). > > > > Although the VM's memory uses 2M huge pages, the MLNX driver still uses 4K > > pages for pin memory, as well as for unpin. So we use huge pages to skip the > > process of pin memory and unpin memory to reduce downtime. > > > > The test environment: > > kernel: linux-5.12 > > MLNX: ConnectX-4 LX > > libvirt command: > > virsh migrate --live --p2p --persistent --copy-storage-inc --listen-address \ > > 0.0.0.0 --rdma-pin-all --migrateuri rdma://192.168.0.2 [VM] qemu+tcp://192.168.0.2/system > > > > Signed-off-by: lizhaoxin > > > > diff --git a/migration/rdma.c b/migration/rdma.c > > index 1cdb4561f3..9823449297 100644 > > --- a/migration/rdma.c > > +++ b/migration/rdma.c > > @@ -1123,13 +1123,26 @@ static int qemu_rdma_reg_whole_ram_blocks(RDMAContext *rdma) > > RDMALocalBlocks *local = &rdma->local_ram_blocks; > > > > for (i = 0; i < local->nb_blocks; i++) { > > - local->block[i].mr = > > - ibv_reg_mr(rdma->pd, > > - local->block[i].local_host_addr, > > - local->block[i].length, > > - IBV_ACCESS_LOCAL_WRITE | > > - IBV_ACCESS_REMOTE_WRITE > > - ); > > + if (strcmp(local->block[i].block_name,"pc.ram") == 0) { > > 'pc.ram' is an x86 architecture specific name, so this will still > leave a problem on other architectures I assume. Yes, and also break even on PC when using NUMA. I think the thing to do here is to call qemu_ram_pagesize on the RAMBlock; if (qemu_ram_pagesize(RAMBlock....) != qemu_real_host_page_size) it's a huge page I guess it's probably best to do that in qemu_rdma_init_one_block or something? I wonder how that all works when there's a mix of different huge page sizes? Dave > > + local->block[i].mr = > > + ibv_reg_mr(rdma->pd, > > + local->block[i].local_host_addr, > > + local->block[i].length, > > + IBV_ACCESS_LOCAL_WRITE | > > + IBV_ACCESS_REMOTE_WRITE | > > + IBV_ACCESS_ON_DEMAND | > > + IBV_ACCESS_HUGETLB > > + ); > > + } else { > > + local->block[i].mr = > > + ibv_reg_mr(rdma->pd, > > + local->block[i].local_host_addr, > > + local->block[i].length, > > + IBV_ACCESS_LOCAL_WRITE | > > + IBV_ACCESS_REMOTE_WRITE > > + ); > > + } > > + > > if (!local->block[i].mr) { > > perror("Failed to register local dest ram block!\n"); > > break; > > Regards, > Daniel > -- > |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| > |: https://libvirt.org -o- https://fstop138.berrange.com :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK