From nobody Mon Feb 9 19:37:45 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of redhat.com designates 170.10.133.124 as permitted sender) client-ip=170.10.133.124; envelope-from=libvir-list-bounces@redhat.com; helo=us-smtp-delivery-124.mimecast.com; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com; dmarc=pass(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1690204047; cv=none; d=zohomail.com; s=zohoarc; b=gE+mCc5YzdtKX1E6rhJfW5qZ/dmA8O89viGMwlihWlmAQRYDKAlf/zdsxNoDSAeqg6GND07CeNfTyv0EPfTqRcOcWIA4fh5VVLO3IDTndyrbZwHhaTOUOKp79I2UTMCWGp8g4qBgt4S870q4VTWB9dFErP7PAPTKt/okcLUyWRw= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1690204047; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=DgfPHen12kn/Tt0KY2EYgK30m6PxOvFEC8h9F1aKAnY=; b=ZkkYZuRypmsa3TgCzP19v7TXm9fVO11w3l6e0Yb23cemoXhpJ31at9eSUkpLOvj9zQS9rB3X4Em4EIT+yG7nfhSQVTfzY/9KfNTemiGPGuPOjNkj3z3XKBziyMy33qJOJbjklBL+cd13cEmEts5ACSndTJ8KhDDr9HDYoMP3tNM= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mx.zohomail.com with SMTPS id 1690204047551496.56349880043115; Mon, 24 Jul 2023 06:07:27 -0700 (PDT) Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-680-hGSK2qB2MECostr6dOSY9g-1; Mon, 24 Jul 2023 09:07:21 -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 mimecast-mx02.redhat.com (Postfix) with ESMTPS id A6B6C86F124; Mon, 24 Jul 2023 13:07:18 +0000 (UTC) Received: from mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (unknown [10.30.29.100]) by smtp.corp.redhat.com (Postfix) with ESMTP id 95069F782E; Mon, 24 Jul 2023 13:07:18 +0000 (UTC) Received: from mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (localhost [IPv6:::1]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id 82FF8194658D; Mon, 24 Jul 2023 13:07:18 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id 05C4F194658D for ; Mon, 24 Jul 2023 13:07:17 +0000 (UTC) Received: by smtp.corp.redhat.com (Postfix) id EA417F783C; Mon, 24 Jul 2023 13:07:16 +0000 (UTC) Received: from secure.mitica (unknown [10.39.194.115]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1D4D110E5E; Mon, 24 Jul 2023 13:07:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1690204046; h=from:from:sender:sender: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:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=DgfPHen12kn/Tt0KY2EYgK30m6PxOvFEC8h9F1aKAnY=; b=GNhHmixUkEkZc2e4RtpVMbZBCq0Lh2fKL4teM1W3fQeTVw/KaA3C3F2w5TJ2OLP0HD3z7w cEGKMIWzlMwfnGJFKbipsViZ/tghCVjR83USkqVqQQ0z5olgScyYkDai5CDfZY0E7v6XSS FU/DixNC9lYLsarZn/Pl0ard58iRN2M= X-MC-Unique: hGSK2qB2MECostr6dOSY9g-1 X-Original-To: libvir-list@listman.corp.redhat.com From: Juan Quintela To: qemu-devel@nongnu.org Subject: [PATCH 16/26] migration: skipped field is really obsolete. Date: Mon, 24 Jul 2023 15:06:29 +0200 Message-Id: <20230724130639.93135-17-quintela@redhat.com> In-Reply-To: <20230724130639.93135-1-quintela@redhat.com> References: <20230724130639.93135-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 X-BeenThere: libvir-list@redhat.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development discussions about the libvirt library & tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , Thomas Huth , Juan Quintela , libvir-list@redhat.com, Markus Armbruster , Peter Xu , Leonardo Bras , Paolo Bonzini , Eric Blake Errors-To: libvir-list-bounces@redhat.com Sender: "libvir-list" X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1690204368806100005 Has return zero for more than 10 years. Specifically we introduced the field in 1.5.0 commit f1c72795af573b24a7da5eb52375c9aba8a37972 Author: Peter Lieven Date: Tue Mar 26 10:58:37 2013 +0100 migration: do not sent zero pages in bulk stage during bulk stage of ram migration if a page is a zero page do not send it at all. the memory at the destination reads as zero anyway. even if there is an madvise with QEMU_MADV_DONTNEED at the target upon receipt of a zero page I have observed that the target starts swapping if the memory is overcommitted. it seems that the pages are dropped asynchronously. this patch also updates QMP to return the number of skipped pages in MigrationStats. but removed its usage in 1.5.3 commit 9ef051e5536b6368a1076046ec6c4ec4ac12b5c6 Author: Peter Lieven Date: Mon Jun 10 12:14:19 2013 +0200 Revert "migration: do not sent zero pages in bulk stage" Not sending zero pages breaks migration if a page is zero at the source but not at the destination. This can e.g. happen if different BIOS versions are used at source and destination. It has also been reported that migration on pseries is completely broken with this patch. This effectively reverts commit f1c72795af573b24a7da5eb52375c9aba8a3797= 2. Reviewed-by: Daniel P. Berrang=C3=A9 Message-ID: <20230612193344.3796-2-quintela@redhat.com> Signed-off-by: Juan Quintela --- docs/about/deprecated.rst | 10 ++++++++++ qapi/migration.json | 12 ++++++++++-- 2 files changed, 20 insertions(+), 2 deletions(-) diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst index 02ea5a839f..1c35f55666 100644 --- a/docs/about/deprecated.rst +++ b/docs/about/deprecated.rst @@ -451,3 +451,13 @@ both, older and future versions of QEMU. The ``blacklist`` config file option has been renamed to ``block-rpcs`` (to be in sync with the renaming of the corresponding command line option). + +Migration +--------- + +``skipped`` MigrationStats field (since 8.1) +'''''''''''''''''''''''''''''''''''''''''''' + +``skipped`` field in Migration stats has been deprecated. It hasn't +been used for more than 10 years. + diff --git a/qapi/migration.json b/qapi/migration.json index 7ccb28e64f..bc9ae3fef7 100644 --- a/qapi/migration.json +++ b/qapi/migration.json @@ -23,7 +23,8 @@ # # @duplicate: number of duplicate (zero) pages (since 1.2) # -# @skipped: number of skipped zero pages (since 1.5) +# @skipped: number of skipped zero pages. Always zero, only provided for +# compatibility (since 1.5) # # @normal: number of normal pages (since 1.2) # @@ -62,11 +63,18 @@ # between 0 and @dirty-sync-count * @multifd-channels. (since # 7.1) # +# Features: +# +# @deprecated: Member @skipped is always zero since 1.5.3 +# # Since: 0.14 +# ## { 'struct': 'MigrationStats', 'data': {'transferred': 'int', 'remaining': 'int', 'total': 'int' , - 'duplicate': 'int', 'skipped': 'int', 'normal': 'int', + 'duplicate': 'int', + 'skipped': { 'type': 'int', 'features': ['deprecated'] }, + 'normal': 'int', 'normal-bytes': 'int', 'dirty-pages-rate': 'int', 'mbps': 'number', 'dirty-sync-count': 'int', 'postcopy-requests': 'int', 'page-size': 'int', --=20 2.40.1