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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 CD991C43603 for ; Fri, 20 Dec 2019 16:10:28 +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 9351D2146E for ; Fri, 20 Dec 2019 16:10:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="GlL1fvrs" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9351D2146E 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]:58468 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iiKrD-000062-MN for qemu-devel@archiver.kernel.org; Fri, 20 Dec 2019 11:10:27 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:52810) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iiKqY-0007qt-K9 for qemu-devel@nongnu.org; Fri, 20 Dec 2019 11:09:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iiKqV-0003Qq-66 for qemu-devel@nongnu.org; Fri, 20 Dec 2019 11:09:44 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:34896 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iiKqU-0003Q2-VV for qemu-devel@nongnu.org; Fri, 20 Dec 2019 11:09:43 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576858181; 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=SOTvQ7u3nhQF/D9sVhCfi2MGv/2bL8ujCj6cC8eKtyE=; b=GlL1fvrsFNPPqqW9ciqoWPw0NyR0D7t4t/zEEB29WPIdEOZz4EG4cUeStOkTLiMbtNzBx7 niRa/LnqZHbbjOY3EGANZqZnHzJd39/PauJSHWOpsn5qwe2KcZhiSJ5ISAF0O4NJmrm/gG 3u6qOpYGkjK5+4GIz8l002S2bDmJEl8= 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-241-6pFd88r0O4i47-b5FSjdBw-1; Fri, 20 Dec 2019 11:09:38 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 221CEB163B; Fri, 20 Dec 2019 16:09:37 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-116-42.ams2.redhat.com [10.36.116.42]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 61A6B5DA76; Fri, 20 Dec 2019 16:09:33 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id A8F3911386A7; Fri, 20 Dec 2019 17:09:31 +0100 (CET) From: Markus Armbruster To: Yury Kotov Subject: Re: [PATCH 0/2] Speed up QMP stream reading References: <20191219160756.22389-1-yury-kotov@yandex-team.ru> Date: Fri, 20 Dec 2019 17:09:31 +0100 In-Reply-To: <20191219160756.22389-1-yury-kotov@yandex-team.ru> (Yury Kotov's message of "Thu, 19 Dec 2019 19:07:54 +0300") Message-ID: <87a77ndlms.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-MC-Unique: 6pFd88r0O4i47-b5FSjdBw-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.81 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: "Daniel P. =?utf-8?Q?Berrang=C3=A9?=" , qemu-devel@nongnu.org, "Dr. David Alan Gilbert" , Denis Plotnikov , yc-core@yandex-team.ru, "Denis V. Lunev" , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Yury Kotov writes: > Hi, > > This series is continuation of another one: > [PATCH] monitor: Fix slow reading > https://lists.gnu.org/archive/html/qemu-devel/2019-11/msg03722.html > > Which also tried to read more than one byte from a stream at a time, > but had some problems with OOB and HMP: > https://lists.gnu.org/archive/html/qemu-devel/2019-11/msg05018.html > > This series is an attempt to fix problems described. Two problems: (1) breaks HMP migrate -d, and (2) need to think through how this affects reading of QMP input, in particular OOB. This series refrains from changing HMP, thus avoids (1). Good. What about (2)? I'm feeling denser than usual today... Can you explain real slow how QMP input works? PATCH 2 appears to splice in a ring buffer. Why is that needed?