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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id C01E3E6FE36 for ; Fri, 22 Sep 2023 14:19:56 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qjgzk-0006wj-LZ; Fri, 22 Sep 2023 10:19:00 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qjgzj-0006wV-Ao for qemu-devel@nongnu.org; Fri, 22 Sep 2023 10:18:59 -0400 Received: from smtp-out1.suse.de ([2001:67c:2178:6::1c]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1qjgzg-0001ql-LP for qemu-devel@nongnu.org; Fri, 22 Sep 2023 10:18:59 -0400 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 16E1921CA4; Fri, 22 Sep 2023 14:18:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1695392333; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=VAvGJQI/dGf1vgh0OYWBpmCQH7kFoLK/nhQu7gj74f8=; b=fJ4S1H+xbveWBpUxInd9Cpr39VsnRb8zwE/qAl0dpHCT2EFMTdOneRfNKy1TQRHnFAOZUX UlpuE1f3tQVQoaTAmZIbaxsrjuKG6Dr1/dkL7fpDChSuj0Mx77HKu4G09n/SfC8rwWkt9m 9Ea5FquwdOaau2Ed/U1jxaTnbrtzXoM= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1695392333; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=VAvGJQI/dGf1vgh0OYWBpmCQH7kFoLK/nhQu7gj74f8=; b=K+QeMTa31P1R+IbWLqhDXr9HAxHuBLGJE+zbpt8CLy3ApoLEhUaXskG7BZGLNq6PrsLBRo aPmIRcXABeJMQ0Bw== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 94B1B13478; Fri, 22 Sep 2023 14:18:52 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 7nAQGEyiDWUTeQAAMHmgww (envelope-from ); Fri, 22 Sep 2023 14:18:52 +0000 From: Fabiano Rosas To: Elena Ufimtseva , quintela@redhat.com, peterx@redhat.com, leobras@redhat.com Cc: elena.ufimtseva@oracle.com, qemu-devel@nongnu.org Subject: Re: [PATCH 0/4] multifd: various fixes In-Reply-To: <20230922065625.21848-1-elena.ufimtseva@oracle.com> References: <20230922065625.21848-1-elena.ufimtseva@oracle.com> Date: Fri, 22 Sep 2023 11:18:50 -0300 Message-ID: <877coi70l1.fsf@suse.de> MIME-Version: 1.0 Content-Type: text/plain Received-SPF: pass client-ip=2001:67c:2178:6::1c; envelope-from=farosas@suse.de; helo=smtp-out1.suse.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Elena Ufimtseva writes: > Hello > > While working and testing various live migration scenarios, > a few issues were found. > > This is my first patches in live migration and I will > appreciate the suggestions from the community if these > patches could be done differently. > > [PATCH 1/4] multifd: wait for channels_ready before sending sync > I am not certain about this change since it seems that > the sync flag could be the part of the packets with pages that are > being sent out currently. > But the traces show this is not always the case: > multifd_send 230.873 pid=55477 id=0x0 packet_num=0x6f4 normal=0x40 flags=0x1 next_packet_size=0x40000 > multifd_send 14.718 pid=55477 id=0x1 packet_num=0x6f5 normal=0x0 flags=0x1 next_packet_size=0x80000 > If the sync packet is indeed can be a standalone one, then waiting for > channels_ready before seem to be appropriate, but waisting iteration on > sync only packet. I haven't looked at this code for a while, so there's some context switching to be made, but you're definitely on the right track here. I actually have an unsent patch doing almost the same as your patch 1/4. I'll comment more there. About the sync being standalone, I would expect that to always be the case since we're incrementing packet_num at that point. > [PATCH 4/4] is also relevant to 1/4, but fixes the over-accounting in > case of sync only packet. > > > Thank you in advance and looking forward for your feedback. > > Elena > > Elena Ufimtseva (4): > multifd: wait for channels_ready before sending sync > migration: check for rate_limit_max for RATE_LIMIT_DISABLED > multifd: fix counters in multifd_send_thread > multifd: reset next_packet_len after sending pages > > migration/migration-stats.c | 8 ++++---- > migration/multifd.c | 11 ++++++----- > 2 files changed, 10 insertions(+), 9 deletions(-)