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 774A0C54E41 for ; Wed, 28 Feb 2024 09:43:53 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rfGTJ-00034X-Kg; Wed, 28 Feb 2024 04:43:29 -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 1rfGTI-00033v-3T for qemu-devel@nongnu.org; Wed, 28 Feb 2024 04:43:28 -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 1rfGTG-000124-9w for qemu-devel@nongnu.org; Wed, 28 Feb 2024 04:43:27 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1709113405; 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=90EYwNN3taKNbrPskwN7+5yupyuP+FKhGjAZkMadByU=; b=HRFFJ2X1FelmteZk+im6Cff9+H+pJSDQxs3oN1UGB3XrxWkeGLbbjBCouRxbyUDbBlr19/ iMAj0TPqp7tnXIc8vdt0vCHtM0MFNtzbopEEu/i7HFZZWoTb//qGlENz1J7IC44IXt2mc/ 2LrKN46OJgfxYbkl6Tq7rV8TVZTSu10= 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-190-CmH25LCSNmG1sBYh2fwuFA-1; Wed, 28 Feb 2024 04:43:22 -0500 X-MC-Unique: CmH25LCSNmG1sBYh2fwuFA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (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 75F1E85A58C; Wed, 28 Feb 2024 09:43:21 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.193.4]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 38691112132A; Wed, 28 Feb 2024 09:43:21 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 430C021E66F9; Wed, 28 Feb 2024 10:43:20 +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 v3 1/7] migration/multifd: Add new migration option zero-page-detection. In-Reply-To: <20240226195654.934709-2-hao.xiang@bytedance.com> (Hao Xiang's message of "Mon, 26 Feb 2024 19:56:48 +0000") References: <20240226195654.934709-1-hao.xiang@bytedance.com> <20240226195654.934709-2-hao.xiang@bytedance.com> Date: Wed, 28 Feb 2024 10:43:20 +0100 Message-ID: <87msrk2abr.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 10.11.54.3 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=-0.088, 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 new parameter controls where the zero page checking is running. > 1. If this parameter is set to 'legacy', zero page checking is > done in the migration main thread. > 2. If this parameter is set to 'none', zero page checking is disabled. > > Signed-off-by: Hao Xiang [...] > diff --git a/qapi/migration.json b/qapi/migration.json > index 5a565d9b8d..1e66272f8f 100644 > --- a/qapi/migration.json > +++ b/qapi/migration.json > @@ -653,6 +653,18 @@ > { 'enum': 'MigMode', > 'data': [ 'normal', 'cpr-reboot' ] } > > +## > +# @ZeroPageDetection: > +# > +# @none: Do not perform zero page checking. > +# > +# @legacy: Perform zero page checking from main migration thread. > +# > +# Since: 9.0 > +## > +{ 'enum': 'ZeroPageDetection', > + 'data': [ 'none', 'legacy' ] } > + > ## > # @BitmapMigrationBitmapAliasTransform: > # > @@ -874,6 +886,9 @@ > # @mode: Migration mode. See description in @MigMode. Default is 'normal'. > # (Since 8.2) > # > +# @zero-page-detection: Whether and how to detect zero pages. More details > +# see description in @ZeroPageDetection. Default is 'legacy'. (since 9.0) > +# I'm not sure we need to point to the member's type. If we want to, we better fix the prose: "For additional information, see @ZeroPageDetection" or similar. Two spaces between sentences for consistency, please. Also, limit line length 70 characters. Together: # @zero-page-detection: Whether and how to detect zero pages. For # additional information, see @ZeroPageDetection. Default is # 'multifd'. (since 9.0) Same for the other two copies. > # Features: > # > # @deprecated: Member @block-incremental is deprecated. Use > @@ -907,7 +922,8 @@ > 'block-bitmap-mapping', > { 'name': 'x-vcpu-dirty-limit-period', 'features': ['unstable'] }, > 'vcpu-dirty-limit', > - 'mode'] } > + 'mode', > + 'zero-page-detection'] } > > ## > # @MigrateSetParameters: > @@ -1066,6 +1082,9 @@ > # @mode: Migration mode. See description in @MigMode. Default is 'normal'. > # (Since 8.2) > # > +# @zero-page-detection: Whether and how to detect zero pages. More details > +# see description in @ZeroPageDetection. Default is 'legacy'. (since 9.0) > +# > # Features: > # > # @deprecated: Member @block-incremental is deprecated. Use > @@ -1119,7 +1138,8 @@ > '*x-vcpu-dirty-limit-period': { 'type': 'uint64', > 'features': [ 'unstable' ] }, > '*vcpu-dirty-limit': 'uint64', > - '*mode': 'MigMode'} } > + '*mode': 'MigMode', > + '*zero-page-detection': 'ZeroPageDetection'} } > > ## > # @migrate-set-parameters: > @@ -1294,6 +1314,9 @@ > # @mode: Migration mode. See description in @MigMode. Default is 'normal'. > # (Since 8.2) > # > +# @zero-page-detection: Whether and how to detect zero pages. More details > +# see description in @ZeroPageDetection. Default is 'legacy'. (since 9.0) > +# > # Features: > # > # @deprecated: Member @block-incremental is deprecated. Use > @@ -1344,7 +1367,8 @@ > '*x-vcpu-dirty-limit-period': { 'type': 'uint64', > 'features': [ 'unstable' ] }, > '*vcpu-dirty-limit': 'uint64', > - '*mode': 'MigMode'} } > + '*mode': 'MigMode', > + '*zero-page-detection': 'ZeroPageDetection'} } > > ## > # @query-migrate-parameters: