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 BF081C5478C for ; Fri, 1 Mar 2024 07:40:59 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rfxVh-0005R2-CS; Fri, 01 Mar 2024 02:40:49 -0500 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 1rfxVb-0005QX-8V for qemu-devel@nongnu.org; Fri, 01 Mar 2024 02:40:44 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rfxVZ-0001iG-N1 for qemu-devel@nongnu.org; Fri, 01 Mar 2024 02:40:42 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1709278840; 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: in-reply-to:in-reply-to:references:references; bh=HtKjMe+fbDWcT8yNOTXNYxPoS3fYcE6aqi8vIhzZ79c=; b=Y8IhqMLJEDyGd9p6G4xmKozoSFvtGx40xm5zF412fXrqVoz+rT68Ym7m0DVibzG1IFo4xA eS+oLRff1Nwd5+RLlGeCiLZBfoxC4opw1sUlk7M3H8QmbnUW0qi8suzghmmG0APYcnSmY0 myMQaJYWENy1ip+1l2SO7HhYe+1YLRo= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-250-sLohgB1VOTymwGrk8KQCuw-1; Fri, 01 Mar 2024 02:40:39 -0500 X-MC-Unique: sLohgB1VOTymwGrk8KQCuw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5DF13106CF99; Fri, 1 Mar 2024 07:40:38 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.193.4]) by smtp.corp.redhat.com (Postfix) with ESMTPS id F20D61C060B1; Fri, 1 Mar 2024 07:40:37 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 9BFAC21E6740; Fri, 1 Mar 2024 08:40:36 +0100 (CET) From: Markus Armbruster To: Hao Xiang Cc: pbonzini@redhat.com, berrange@redhat.com, eduardo@habkost.net, peterx@redhat.com, farosas@suse.de, eblake@redhat.com, armbru@redhat.com, thuth@redhat.com, lvivier@redhat.com, jdenemar@redhat.com, marcel.apfelbaum@gmail.com, philmd@linaro.org, wangyanan55@huawei.com, qemu-devel@nongnu.org Subject: Re: [PATCH v4 6/7] migration/multifd: Add zero pages and zero bytes counter to migration status interface. In-Reply-To: <20240301022829.3390548-7-hao.xiang@bytedance.com> (Hao Xiang's message of "Fri, 1 Mar 2024 02:28:28 +0000") References: <20240301022829.3390548-1-hao.xiang@bytedance.com> <20240301022829.3390548-7-hao.xiang@bytedance.com> Date: Fri, 01 Mar 2024 08:40:36 +0100 Message-ID: <87ttlqpfgr.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.096, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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 Hao Xiang writes: > This change extends the MigrationStatus interface to track zero pages > and zero bytes counter. > > Signed-off-by: Hao Xiang [...] > diff --git a/qapi/migration.json b/qapi/migration.json > index ca9561fbf1..03b850bab7 100644 > --- a/qapi/migration.json > +++ b/qapi/migration.json > @@ -63,6 +63,10 @@ > # between 0 and @dirty-sync-count * @multifd-channels. (since > # 7.1) > # > +# @zero-pages: number of zero pages (since 9.0) > +# > +# @zero-bytes: number of zero bytes sent (since 9.0) > +# Discussion of v3 has led me to believe: 1. A page is either migrated as a normal page or as a zero page. 2. The following equations hold: @normal-bytes = @normal * @page-size @zero-bytes = @zero-pages * @page-size 3. @zero-pages is the same as @duplicate, with a better name. We intend to drop @duplicate eventually. If this is correct, I'd like you to A. Name it @zero for consistency with @normal. Disregard my advice to name it @zero-pages; two consistent bad names are better than one bad name, one good name, and inconsistency. B. Add @zero and @zero-bytes next to @normal and @normal-bytes. C. Deprecate @duplicate (item 3). Separate patch, please. D. Consider documenting more clearly what normal and zero pages are (item 1), and how @FOO, @FOO-pages and @page-size are related (item 2). Could be done in a followup patch. > # Features: > # > # @deprecated: Member @skipped is always zero since 1.5.3 > @@ -81,7 +85,8 @@ > 'multifd-bytes': 'uint64', 'pages-per-second': 'uint64', > 'precopy-bytes': 'uint64', 'downtime-bytes': 'uint64', > 'postcopy-bytes': 'uint64', > - 'dirty-sync-missed-zero-copy': 'uint64' } } > + 'dirty-sync-missed-zero-copy': 'uint64', > + 'zero-pages': 'int', 'zero-bytes': 'size' } } > [...]