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 1B4BBC7EE24 for ; Fri, 2 Jun 2023 10:15:27 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q51ns-0006nt-Ev; Fri, 02 Jun 2023 06:14:40 -0400 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 1q51nr-0006nk-7K for qemu-devel@nongnu.org; Fri, 02 Jun 2023 06:14:39 -0400 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 1q51np-0005fr-1i for qemu-devel@nongnu.org; Fri, 02 Jun 2023 06:14:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1685700875; 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:in-reply-to:in-reply-to: references:references; bh=KboCMttqzmq9fnad+u2dDJNypnXIV/u5wGG3Pt0f5Pg=; b=Vthd5TebjSGXGJkRtOrlmsMl5CfegWYy0WROVv+TTE8ZWrhWFI6LFK4n1IxKaRWMlJcYq3 whPvcZ+dRTZu7yNha5YNb/BKgl4+wn4l8yMvkUN1q+LEvZQ0PvHKxZFrozKZrDnbXTW0wJ KEzuYNF4nYz+E4wO5/RXkcxNgY6pVvg= 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-36-xOyY-sq5NhWOlmgCLT1h3g-1; Fri, 02 Jun 2023 06:14:31 -0400 X-MC-Unique: xOyY-sq5NhWOlmgCLT1h3g-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id CD6CC185A78B; Fri, 2 Jun 2023 10:14:30 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.158]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0848D492B00; Fri, 2 Jun 2023 10:14:29 +0000 (UTC) Date: Fri, 2 Jun 2023 11:14:26 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Juan Quintela Cc: qemu-devel@nongnu.org, peter.maydell@linaro.org, Richard Henderson Subject: Re: Big TCG slowdown when using zstd with aarch64 Message-ID: References: <87y1l2rixp.fsf@secure.mitica> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <87y1l2rixp.fsf@secure.mitica> User-Agent: Mutt/2.2.9 (2022-11-12) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.166, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Thu, Jun 01, 2023 at 11:06:42PM +0200, Juan Quintela wrote: > > Hi > > Before I continue investigating this further, do you have any clue what > is going on here. I am running qemu-system-aarch64 on x86_64. FYI, the trigger for this behaviour appears to be your recent change to stats accounting in: commit cbec7eb76879d419e7dbf531ee2506ec0722e825 (HEAD) Author: Juan Quintela Date: Mon May 15 21:57:09 2023 +0200 migration/multifd: Compute transferred bytes correctly In the past, we had to put the in the main thread all the operations related with sizes due to qemu_file not beeing thread safe. As now all counters are atomic, we can update the counters just after the do the write. As an aditional bonus, we are able to use the right value for the compression methods. Right now we were assuming that there were no compression at all. Signed-off-by: Juan Quintela Reviewed-by: Peter Xu Message-Id: <20230515195709.63843-17-quintela@redhat.com> Before that commit the /aarch64/migration/multifd/tcp/plain/{none,zlib,zstd} tests all took 21 seconds eachs. After that commit the 'none' test takes about 3 seconds, and the zlib/zstd test take about 1 second, except when zstd is suddenly very slow. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|