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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 A6D4EC10F0E for ; Thu, 4 Apr 2019 13:28:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7D47A206B7 for ; Thu, 4 Apr 2019 13:28:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729486AbfDDN2n (ORCPT ); Thu, 4 Apr 2019 09:28:43 -0400 Received: from mail-qt1-f193.google.com ([209.85.160.193]:33617 "EHLO mail-qt1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726269AbfDDN2n (ORCPT ); Thu, 4 Apr 2019 09:28:43 -0400 Received: by mail-qt1-f193.google.com with SMTP id k14so3214386qtb.0 for ; Thu, 04 Apr 2019 06:28:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=7yyf+HgxleLYBHaKJbIu80u0jEokOC4UH8AehtEvcEM=; b=MM0lL9E+r6d+hZgeFBX2WIxyAmlUBqi3r3LSOUw4eURXRTvwIrNwI+bjnml/7wCoYS 1kguwPZeW1HH+dM4474c3k4Ty/WlTOeQqFb4kxzViOV6qnBI6BBse0pswbZp4Al1+T8z PCdwYQmT+yko2zd+SN6IzAPH3OyCO7m5neDsB4O2R7EV1CF/EZclNc59DwdpLvvXiyO5 Bxe1u2e5AW/cSLJHZzVznWTi/BZHj6kL1jyhdgeCNz02PHABvTPHk3jDWg2okg/m1mdg k5PdMUvPDDXRkw5WUjFp+vZm3t6hGLSN0C9sjUb83zAQdhHWVJQToQsHwXqiwuky7whu d0hg== X-Gm-Message-State: APjAAAX0QRG/s6+ndMhR0Uo6/7Tf7U+qLY56WW0tWlGKSSnVqmcn9JO0 M7XPH6H+DikOqtxz4eN6RwapTw== X-Google-Smtp-Source: APXvYqyGfRXpzQFNaSliZNlz6/G8SzOU+HMRc8xYFoGZ0ZQbt0QhYGmCO8b8oYZ6Q0w9Htvlju38sw== X-Received: by 2002:ac8:28e9:: with SMTP id j38mr5244597qtj.297.1554384522144; Thu, 04 Apr 2019 06:28:42 -0700 (PDT) Received: from redhat.com (pool-173-76-246-42.bstnma.fios.verizon.net. [173.76.246.42]) by smtp.gmail.com with ESMTPSA id q51sm12443768qtc.38.2019.04.04.06.28.39 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 04 Apr 2019 06:28:41 -0700 (PDT) Date: Thu, 4 Apr 2019 09:28:38 -0400 From: "Michael S. Tsirkin" To: Alexander Duyck Cc: David Hildenbrand , Nitesh Narayan Lal , kvm list , LKML , linux-mm , Paolo Bonzini , lcapitulino@redhat.com, pagupta@redhat.com, wei.w.wang@intel.com, Yang Zhang , Rik van Riel , dodgen@google.com, Konrad Rzeszutek Wilk , dhildenb@redhat.com, Andrea Arcangeli Subject: Re: On guest free page hinting and OOM Message-ID: <20190404083321-mutt-send-email-mst@kernel.org> References: <29e11829-c9ac-a21b-b2f1-ed833e4ca449@redhat.com> <20190401104608-mutt-send-email-mst@kernel.org> <6a612adf-e9c3-6aff-3285-2e2d02c8b80d@redhat.com> <1249f9dd-d22d-9e19-ee33-767581a30021@redhat.com> <0fdc41fb-b2ba-c6e6-36b9-97ad5a6eb54c@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 02, 2019 at 04:43:03PM -0700, Alexander Duyck wrote: > Yes, but hopefully it should be a small enough amount that nobody will > notice. In many cases devices such as NICs can consume much more than > this regularly for just their Rx buffers and it is not an issue. There > has to be a certain amount of overhead that any given device is > allowed to consume. If we contain the balloon hinting to just 64M that > should be a small enough amount that nobody would notice in practice. I am still inclined to add ability for balloon to exit to host on OOM if any hints are outstanding. If nothing else will be helpful for stats. -- MST