From owner-freebsd-arch@FreeBSD.ORG Sun Feb 3 10:10:58 2013 Return-Path: Delivered-To: freebsd-arch@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 1228E7F0 for ; Sun, 3 Feb 2013 10:10:58 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 38F4569 for ; Sun, 3 Feb 2013 10:10:56 +0000 (UTC) Received: from porto.starpoint.kiev.ua (porto-e.starpoint.kiev.ua [212.40.38.100]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id MAA07034; Sun, 03 Feb 2013 12:10:54 +0200 (EET) (envelope-from avg@FreeBSD.org) Received: from localhost ([127.0.0.1]) by porto.starpoint.kiev.ua with esmtp (Exim 4.34 (FreeBSD)) id 1U1wXG-0006BR-FM; Sun, 03 Feb 2013 12:10:54 +0200 Message-ID: <510E37AE.8060206@FreeBSD.org> Date: Sun, 03 Feb 2013 12:10:54 +0200 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:17.0) Gecko/20130121 Thunderbird/17.0.2 MIME-Version: 1.0 To: Konstantin Belousov Subject: Re: axe vm.max_wired References: <20120517055425.GA802@infradead.org> <4FC762DD.90101@FreeBSD.org> <4FC81D9C.2080801@FreeBSD.org> <4FC8E29F.2010806@shatow.net> <4FC95A10.7000806@freebsd.org> <4FC9F94B.8060708@FreeBSD.org> <51098977.4000603@FreeBSD.org> <20130131091853.GI2522@kib.kiev.ua> <510B7B92.4030804@FreeBSD.org> <20130202162509.GZ2522@kib.kiev.ua> In-Reply-To: <20130202162509.GZ2522@kib.kiev.ua> X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-arch@FreeBSD.org X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 03 Feb 2013 10:10:58 -0000 on 02/02/2013 18:25 Konstantin Belousov said the following: > On Fri, Feb 01, 2013 at 10:23:46AM +0200, Andriy Gapon wrote: >> So, I still think that vm.max_wired as it is used now is too arbitrary and too >> indiscriminate to be useful. > It is sized well to the default size of the buffer map, which takes 10% > of the physical RAM of the machine. Since buffers wiring the pages, be > it VMIO or malloc buffer, this leaves 20% for other things, like mbufs, > page tables and user wires. That's the attitude that I don't agree with. "We leave 20% for user wirings, that should be enough for everyone." If it's not enough then you must tune. I rather prefer an approach where we say this is the least amount of memory that should stay unwired. The rest is up to a user. >> There are other tools to limit page wiring by userland e.g. memlocked limit. > The memlock limit is per-process. It is completely useless as the safety > measure. There is also a limit on number of processes, etc. >> But, as I've said in the original email, I can agree with vm.max_wired >> usefulness if it is set to something more reasonable by default. >> IMO, it should not be a fixed percentage of available memory, it should be >> derived from other VM thresholds related to paging. > > Might be. Please provide a suggestion or better, a change. On my to do list. -- Andriy Gapon