From owner-freebsd-current@FreeBSD.ORG Sun Nov 21 23:29:12 2010 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 47F57106564A for ; Sun, 21 Nov 2010 23:29:12 +0000 (UTC) (envelope-from onemda@gmail.com) Received: from mail-wy0-f182.google.com (mail-wy0-f182.google.com [74.125.82.182]) by mx1.freebsd.org (Postfix) with ESMTP id A93928FC08 for ; Sun, 21 Nov 2010 23:29:11 +0000 (UTC) Received: by wyb35 with SMTP id 35so5642564wyb.13 for ; Sun, 21 Nov 2010 15:29:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:mime-version:received:in-reply-to :references:from:date:message-id:subject:to:cc:content-type :content-transfer-encoding; bh=yFCqiKQ9LOHDmKQgIXvr14oEpomcgSGXERhNs+sEay4=; b=Sq5ZqBPFgpaKWpLb17j1Y/sr7KUpXWT+VZEAYNGtQfuPKum+VkEDup52HUTw5NFEnB nt8xEK/GAHc9p7Ux0VZ27M/Sfme3DvaVcxUYmekujowWt+u575ZALXMG1MrloSiKdBeT XwirgWEhRm6TCYGeSiwrOeaQ7iuNwyAs+qSKc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:content-transfer-encoding; b=F7sBzEWiEAdbB2OWgIrFzPL4RRVn4jdWifexE1mbWUGcuMIhhUrQpHAacEy89f7gcA efIbs2ue9DnFqkrb6yuXKBappZJoaqy8p3dlx7SV2zqabKwfkWZHCYg1Ny/FJbHrvo3V 44dNVPVs0wdAqHRNI8BdWLeIgZNt/g12TQuYE= Received: by 10.216.164.194 with SMTP id c44mr4159354wel.107.1290382147276; Sun, 21 Nov 2010 15:29:07 -0800 (PST) MIME-Version: 1.0 Received: by 10.216.234.82 with HTTP; Sun, 21 Nov 2010 15:28:47 -0800 (PST) In-Reply-To: References: <20101121214720.356984cc@core.draftnet> From: Paul B Mahol Date: Sun, 21 Nov 2010 23:28:47 +0000 Message-ID: To: Ivan Voras Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: freebsd-current@freebsd.org Subject: Re: tmpfs out of space (ZFS related?) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 21 Nov 2010 23:29:12 -0000 On Sun, Nov 21, 2010 at 10:42 PM, Ivan Voras wrote: > On 11/21/10 23:19, Eir Nym wrote: >> >> On 22 November 2010 01:00, Eir Nym =A0wrote: >>> >>> On 22 November 2010 00:47, Bruce Cran =A0wrote: >>>> >>>> On Mon, 22 Nov 2010 00:43:03 +0300 >>>> Eir Nym =A0wrote: >>>> >>>>> Which type of MFS do you use? I think you shold use "swap-backed" for >>>>> your /tmp, not "malloc-based". Last type is only for in-kernel file >>>>> system. >>>> >>>> It's tmpfs(5), not md(4). >>>> >>> >> >> I wonder if you can create FIFO and sockets with md(4). md(4) is >> geometry, not filesystem. > > md is a GEOM class which presents several types of devices backed by virt= ual > memory. You can create file systems on top of those and mount them. > > The downside is that each of those layers has its own copy of the origina= l > data (and them some). > > tmpfs OTOH is a "real" memory file system, without the need for a backing > device, and it is more efficient with respect to data copies (not perfect= - > it still AFAIK has to maintain something like 2 copies). AFAIK, if this was ever correct it is not any more. Data copies can mean anything. I use >1.5 GB file in tmpfs on 2GB RAM and 0B SWAP without problems. >> tmpfs(5) doesn't support this file types as I can see in FreeBSD source >> code. > > Maybe it is handled by default code, but they are supported. I have used > tmpfs extensively for the last few years for mostly static servers (i.e. > /tmp contains some sockets, a small number of short-lived temporary files= , > etc) - and it so far worked very well. This is actually the first time it > failed me in some way. It can be anything: overflow, race, memory corruption ... Find way to reproduce it 100%.