From owner-svn-src-all@FreeBSD.ORG Wed Jun 25 12:41:43 2014 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id B064C3A8; Wed, 25 Jun 2014 12:41:43 +0000 (UTC) Received: from mail-wg0-x22b.google.com (mail-wg0-x22b.google.com [IPv6:2a00:1450:400c:c00::22b]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 87F90239C; Wed, 25 Jun 2014 12:41:42 +0000 (UTC) Received: by mail-wg0-f43.google.com with SMTP id b13so1901864wgh.26 for ; Wed, 25 Jun 2014 05:41:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:reply-to:sender:in-reply-to:references:date:message-id :subject:from:to:cc:content-type; bh=tdU91326w9U0TbyTletuGuNuL78Kb+G1oIFtYinbn3Y=; b=WyPMss6qWZdf2kBtEEJFo4jSyRHtDoRrQk9luRMHufGiHlGb/qP7uR0CZSSypq6Sou o4brkoqLvg7pz03qTtgEB//LnQkshwkRLuF6ZATpPp1arbX8gaibf1sw/9Zmk9VNo748 sqCxk9jBIYqSHXh64ZFrhSzaiXqKkzhIczyXMto6hcik/Bn2t0SqhdmJqh5cqQXEMRwj kVP7Rtz9cnOD5zJ+kIhu8tMAmafSzEfLzViV+I7LZbd6KkBWpYEmgkUV+H8tuRjUx2oM UTmivK/5nkJCX8g28hb52qzhxhsaoiAFBkAyifcfJvMTUXmtS/IdSaVdpCd69zYyeNtt 6B7A== MIME-Version: 1.0 X-Received: by 10.180.198.197 with SMTP id je5mr1133396wic.48.1403700098081; Wed, 25 Jun 2014 05:41:38 -0700 (PDT) Reply-To: attilio@FreeBSD.org Sender: asmrookie@gmail.com Received: by 10.217.46.129 with HTTP; Wed, 25 Jun 2014 05:41:38 -0700 (PDT) In-Reply-To: <20140625120932.GM28199@FreeBSD.org> References: <201406250951.s5P9p8YR017159@svn.freebsd.org> <20140625120932.GM28199@FreeBSD.org> Date: Wed, 25 Jun 2014 14:41:38 +0200 X-Google-Sender-Auth: HZ0Hu44y8vXBRoUiXAvqbB0VtYU Message-ID: Subject: Re: svn commit: r267858 - in head/sys/dev: virtio/balloon xen/balloon From: Attilio Rao To: Gleb Smirnoff Content-Type: text/plain; charset=UTF-8 Cc: Alan Cox , "svn-src-head@freebsd.org" , "svn-src-all@freebsd.org" , =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= , "src-committers@freebsd.org" X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 25 Jun 2014 12:41:43 -0000 On Wed, Jun 25, 2014 at 2:09 PM, Gleb Smirnoff wrote: > On Wed, Jun 25, 2014 at 01:58:29PM +0200, Attilio Rao wrote: > A> > Log: > A> > xen/virtio: fix balloon drivers to not mark pages as WIRED > A> > > A> > Prevent the Xen and VirtIO balloon drivers from marking pages as > A> > wired. This prevents them from increasing the system wired page count, > A> > which can lead to mlock failing because of hitting the limit in > A> > vm.max_wired. > A> > A> This change is conceptually wrong. > A> The pages balloon is allocating are unmanaged and they should be wired > A> by definition. Alan and I are considering enforcing this (mandatory > A> wired pages for unmanaged pages allocation) directly in the KPI. > A> This in practice just seem an artifact to deal with scarce wired > A> memory limit. I suggest that for the XEN case this limit gets bumped > A> rather relying on similar type of hacks. > > Proper limit would be to count pages wired by userland via mlock(2) > and enforce limit only on those pages. Pages wired by kernel should > be either unlimited or controled by a separate limit. FWIW, I mostly agree with this. I think that the kernel and userland limits should be split apart. But for the time being, rising the limit is better. Attilio -- Peace can only be achieved by understanding - A. Einstein