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 ws5-mx01.kavi.com (ws5-mx01.kavi.com [34.193.7.191]) (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 69022C197A0 for ; Thu, 16 Nov 2023 07:36:09 +0000 (UTC) Received: from lists.oasis-open.org (oasis.ws5.connectedcommunity.org [10.110.1.242]) by ws5-mx01.kavi.com (Postfix) with ESMTP id AEEB842D71 for ; Thu, 16 Nov 2023 07:36:08 +0000 (UTC) Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 87DFD986DDE for ; Thu, 16 Nov 2023 07:36:08 +0000 (UTC) Received: from host09.ws5.connectedcommunity.org (host09.ws5.connectedcommunity.org [10.110.1.97]) by lists.oasis-open.org (Postfix) with QMQP id 620D4986DD2; Thu, 16 Nov 2023 07:36:08 +0000 (UTC) Mailing-List: contact virtio-comment-help@lists.oasis-open.org; run by ezmlm List-ID: Sender: Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 50D7A986DD3 for ; Thu, 16 Nov 2023 07:36:08 +0000 (UTC) X-Virus-Scanned: amavisd-new at kavi.com X-MC-Unique: G-X2Kq-2N_OdO8v5xuhUvA-1 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700120162; x=1700724962; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=OfR7M8YBKNg2h1c5hAr3JuGfpXOhaSjzOj1Deo/cA/0=; b=XSiy2gHpswc7L5iEI1QMYHJOpC7USvdjOWHcJiTrq1DZdka+MROEV2UMlAT30ug8qe eEI0QfiKep+DuEJia89uNN/oM89jm2BXuOsjpz7AwAhUjK0AiUhSl6Wgm4+VFcUciOWq EzsIhkeVgIW/URPipckT1g1rfpQhTPulR+Sei59YA5ZVj21pHrGvdB/thTmeX55s0ohG 5R4j3j3s9TfHt2UG2PpADQ4KgbfkaGZkK4uS9Iw43LhsnM82tEFYzSpI7DCsi6+tp7YX yCu38kT664GZxT9cXWLmrIUYWIQXQHE6N9lGSeDFBzpInjc8lSyMKYXLk0FxecG/iICq JfoQ== X-Gm-Message-State: AOJu0YzZUVKNYS/foBXwXHkfOp7iP9xwAK+or7+56i6RAnk4a3qUYn/m pbLMGP4KMgMp2rS07/xv9+ke651IjVcaSpX3JSlWWbPmg/KoWGuoLD2MEO9vvYAr4XnZ/dnT9Pf Y3iJeJG+XU9xGwNUoBEp4+K9WB9uQ2UJW9g== X-Received: by 2002:a05:600c:2217:b0:408:3975:e225 with SMTP id z23-20020a05600c221700b004083975e225mr12420943wml.40.1700120162632; Wed, 15 Nov 2023 23:36:02 -0800 (PST) X-Google-Smtp-Source: AGHT+IE4/HzxrgzqbgptB8LzQUNpU5uAq1L8uLRJY6nqCvEH8XdoLod0MF+ydoRzOX48KTYgWxnQ6w== X-Received: by 2002:a05:600c:2217:b0:408:3975:e225 with SMTP id z23-20020a05600c221700b004083975e225mr12420927wml.40.1700120162226; Wed, 15 Nov 2023 23:36:02 -0800 (PST) Date: Thu, 16 Nov 2023 02:35:59 -0500 From: "Michael S. Tsirkin" To: Parav Pandit Cc: Jason Wang , "virtio-comment@lists.oasis-open.org" , "cohuck@redhat.com" , "sburla@marvell.com" , Shahaf Shuler , Maor Gottlieb , Yishai Hadas , "lingshan.zhu@intel.com" Message-ID: <20231116023443-mutt-send-email-mst@kernel.org> References: <20231116004037-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 In-Reply-To: <20231116004037-mutt-send-email-mst@kernel.org> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [virtio-comment] Re: [PATCH v3 6/8] admin: Add theory of operation for write recording commands On Thu, Nov 16, 2023 at 12:51:40AM -0500, Michael S. Tsirkin wrote: > On Thu, Nov 16, 2023 at 05:29:54AM +0000, Parav Pandit wrote: > > We should expose a limit of the device in the proposed WRITE_RECORD_CAP_QUERY command, that how much range it can track. > > So that future provisioning framework can use it. > > > > I will cover this in v5 early next week. > > I do worry about how this can even work though. If you want a generic > device you do not get to dictate how much memory VM has. > > Aren't we talking bit per page? With 1TByte of memory to track -> > 256Gbit -> 32Gbit -> 8Gbyte per VF? Ugh. Actually of course: With 1TByte of memory to track -> 256Mbit -> 32Mbit -> 8Mbyte per VF 8Gbyte per *PF* with 1K VFs. > And you happily say "we'll address this in the future" while at the same > time fighting tooth and nail against adding single bit status registers > because scalability? > > > I have a feeling doing this completely theoretical like this is problematic. > Maybe you have it all laid out neatly in your head but I suspect > not all of TC can picture it clearly enough based just on spec text. > > We do sometimes ask for POC implementation in linux / qemu to > demonstrate how things work before merging code. We skipped this > for admin things so far but I think it's a good idea to start doing > it here. > > What makes me pause a bit before saying please do a PoC is > all the opposition that seems to exist to even using admin > commands in the 1st place. I think once we finally stop > arguing about whether to use admin commands at all then > a PoC will be needed before merging. > > > -- > MST This publicly archived list offers a means to provide input to the OASIS Virtual I/O Device (VIRTIO) TC. In order to verify user consent to the Feedback License terms and to minimize spam in the list archive, subscription is required before posting. Subscribe: virtio-comment-subscribe@lists.oasis-open.org Unsubscribe: virtio-comment-unsubscribe@lists.oasis-open.org List help: virtio-comment-help@lists.oasis-open.org List archive: https://lists.oasis-open.org/archives/virtio-comment/ Feedback License: https://www.oasis-open.org/who/ipr/feedback_license.pdf List Guidelines: https://www.oasis-open.org/policies-guidelines/mailing-lists Committee: https://www.oasis-open.org/committees/virtio/ Join OASIS: https://www.oasis-open.org/join/