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=-3.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 6DE54C282DD for ; Wed, 8 Jan 2020 13:34:32 +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 36C5B20643 for ; Wed, 8 Jan 2020 13:34:32 +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="SdOik6Nj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 36C5B20643 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]:43966 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ipBTi-0006EX-V6 for qemu-devel@archiver.kernel.org; Wed, 08 Jan 2020 08:34:30 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:41976) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ipBSN-00051v-0W for qemu-devel@nongnu.org; Wed, 08 Jan 2020 08:33:07 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ipBSL-0002VQ-9l for qemu-devel@nongnu.org; Wed, 08 Jan 2020 08:33:06 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:47469 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ipBSL-0002UA-67 for qemu-devel@nongnu.org; Wed, 08 Jan 2020 08:33:05 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1578490384; h=from:from:reply-to: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=VQR2RCi3gks8yKm9J3cqt6uLn8ZXaWfEmTgCPtqzKhE=; b=SdOik6NjcbFyLyeb8k/+/+3MdmfPIdvmqXkjmB1oXVjuIrXbPwBZ4AxvVabqrAn9swdsli F4mdGzqCXwJimcgLKEy1T2pfAHpYinUUynXdh2bOC3PGJmsN4gCl7IcmZpzfXjv+pk+n+l 1XZpFZDItpoK2yG4I12HtpM/qMhqqHo= 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-382-GWP_HXvHPKSYk3o6oiqwaQ-1; Wed, 08 Jan 2020 08:33:00 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 68EC8801E6C; Wed, 8 Jan 2020 13:32:59 +0000 (UTC) Received: from redhat.com (unknown [10.36.118.112]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 90AD019C69; Wed, 8 Jan 2020 13:32:58 +0000 (UTC) From: Juan Quintela To: Yury Kotov Subject: Re: [PATCH v2] migration/ram: Yield periodically to the main loop In-Reply-To: <87imlmgk01.fsf@secure.laptop> (Juan Quintela's message of "Wed, 08 Jan 2020 14:23:10 +0100") References: <20191125133632.21387-1-yury-kotov@yandex-team.ru> <87imlmgk01.fsf@secure.laptop> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) Date: Wed, 08 Jan 2020 14:32:54 +0100 Message-ID: <87eewagjjt.fsf@secure.laptop> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: GWP_HXvHPKSYk3o6oiqwaQ-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: 205.139.110.120 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: , Reply-To: quintela@redhat.com Cc: "open list:All patches CC here" , yc-core@yandex-team.ru, "Dr. David Alan Gilbert" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Juan Quintela wrote: > Yury Kotov wrote: >> Usually, incoming migration coroutine yields to the main loop >> while its IO-channel is waiting for data to receive. But there is a case >> when RAM migration and data receive have the same speed: VM with huge >> zeroed RAM. In this case, IO-channel won't read and thus the main loop >> is stuck and for instance, it doesn't respond to QMP commands. >> >> For this case, yield periodically, but not too often, so as not to >> affect the speed of migration. >> >> Signed-off-by: Yury Kotov > > Reviewed-by: Juan Quintela Nack. The idea is good. But it fails migration-test to fail from time to time (50% of the time on my laptop). Will investigate why this is failing. Later, Juan.