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 70845CDB465 for ; Thu, 19 Oct 2023 14:52:35 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qtUNx-0001T2-11; Thu, 19 Oct 2023 10:52:29 -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 1qtUNt-0001Dz-RH for qemu-devel@nongnu.org; Thu, 19 Oct 2023 10:52:27 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qtUNs-0006r2-1R for qemu-devel@nongnu.org; Thu, 19 Oct 2023 10:52:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1697727143; 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=30zhS09/o2RZjGX/T6liKqJmGgqeMBJz2kuNpjtRqCo=; b=WD28a/sQ3xzVytwsUPiKOmh3w1qxCdqaSfMvoLQCNfxqm0OY19HISQHlJzT7ZyBWvayw3v cA3JOcqCVeh36v2kfHP3aavXBeA7MW41g3WwapHiZ9QAe0P++R8DGckmv63l4qpQaD7ect dgsAdY9zy84Z6zwaKulBxrn1IvIbJdc= 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-671-1MTJXhm5M0yAzvrgYUxrLA-1; Thu, 19 Oct 2023 10:52:19 -0400 X-MC-Unique: 1MTJXhm5M0yAzvrgYUxrLA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id CC8BC10201F0; Thu, 19 Oct 2023 14:52:18 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.60]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CBF2540C6F7B; Thu, 19 Oct 2023 14:52:16 +0000 (UTC) Date: Thu, 19 Oct 2023 15:52:14 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Juan Quintela Cc: Yuan Liu , peterx@redhat.com, farosas@suse.de, leobras@redhat.com, qemu-devel@nongnu.org, nanhai.zou@intel.com Subject: Re: [PATCH 0/5] Live Migration Acceleration with IAA Compression Message-ID: References: <20231018221224.599065-1-yuan1.liu@intel.com> <87cyxa6dso.fsf@secure.mitica> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <87cyxa6dso.fsf@secure.mitica> User-Agent: Mutt/2.2.9 (2022-11-12) X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.2 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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 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, Oct 19, 2023 at 01:40:23PM +0200, Juan Quintela wrote: > Yuan Liu wrote: > > Hi, > > > > I am writing to submit a code change aimed at enhancing live migration > > acceleration by leveraging the compression capability of the Intel > > In-Memory Analytics Accelerator (IAA). > > > > Enabling compression functionality during the live migration process can > > enhance performance, thereby reducing downtime and network bandwidth > > requirements. However, this improvement comes at the cost of additional > > CPU resources, posing a challenge for cloud service providers in terms of > > resource allocation. To address this challenge, I have focused on offloading > > the compression overhead to the IAA hardware, resulting in performance gains. > > > > The implementation of the IAA (de)compression code is based on Intel Query > > Processing Library (QPL), an open-source software project designed for > > IAA high-level software programming. > > > > Best regards, > > Yuan Liu > > After reviewing the patches: > > - why are you doing this on top of old compression code, that is > obsolete, deprecated and buggy > > - why are you not doing it on top of multifd. > > You just need to add another compression method on top of multifd. > See how it was done for zstd: I'm not sure that is ideal approach. IIUC, the IAA/QPL library is not defining a new compression format. Rather it is providing a hardware accelerator for 'deflate' format, as can be made compatible with zlib: https://intel.github.io/qpl/documentation/dev_guide_docs/c_use_cases/deflate/c_deflate_zlib_gzip.html#zlib-and-gzip-compatibility-reference-link With multifd we already have a 'zlib' compression format, and so this IAA/QPL logic would effectively just be a providing a second implementation of zlib. Given the use of a standard format, I would expect to be able to use software zlib on the src, mixed with IAA/QPL zlib on the target, or vica-verca. IOW, rather than defining a new compression format for this, I think we could look at a new migration parameter for "compression-accelerator": ["auto", "none", "qpl"] with 'auto' the default, such that we can automatically enable IAA/QPL when 'zlib' format is requested, if running on a suitable host. 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 :|