Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754143AbbGaRog (ORCPT ); Fri, 31 Jul 2015 13:44:36 -0400 Received: from mail.phunq.net ([184.71.0.62]:47919 "EHLO starbase.phunq.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752607AbbGaRo3 convert rfc822-to-8bit (ORCPT ); Fri, 31 Jul 2015 13:44:29 -0400 X-Greylist: delayed 1020 seconds by postgrey-1.27 at vger.kernel.org; Fri, 31 Jul 2015 13:44:29 EDT From: Daniel Phillips To: Raymond Jennings Cc: OGAWA Hirofumi , David Lang , Rik van Riel , Jan Kara , , Linux Kernel Mailing List , Subject: Re: [FYI] tux3: Core changes Date: Fri, 31 Jul 2015 10:27:13 -0700 User-Agent: Trojita/v0.5-14-g8a2496c; Qt/4.8.6; X11; Linux; Ubuntu 15.04 MIME-Version: 1.0 Message-ID: <1981a91e-30a9-43ce-9a05-14aa777e46a5@phunq.net> In-Reply-To: References: <67294911-1776-46b8-916d-0e5642a38725@phunq.net> <20150526070910.GA3307@quack.suse.cz> <20150526090058.GA8024@quack.suse.cz> <5564D60E.6000306@phunq.net> <20150527084138.GD2590@quack.suse.cz> <87a8vtdqfz.fsf@mail.parknet.co.jp> <20150623161247.GP2427@quack.suse.cz> <87k2ueepd6.fsf@mail.parknet.co.jp> <20150709160528.GK2900@quack.suse.cz> <874mklaqbn.fsf@mail.parknet.co.jp> Organization: tux3.org Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1189 Lines: 26 On Friday, July 31, 2015 8:37:35 AM PDT, Raymond Jennings wrote: > Returning ENOSPC when you have free space you can't yet prove is safer than > not returning it and risking a data loss when you get hit by a write/commit > storm. :) Remember when delayed allocation was scary and unproven, because proving that ENOSPC will always be returned when needed is extremely difficult? But the performance advantage was compelling, so we just worked at it until it worked. There were times when it didn't work properly, but the code was in the tree so it got fixed. It's like that now with page forking - a new technique with compelling advantages, and some challenges. In the past, we (the Linux community) would rise to the challenge and err on the side of pushing optimizations in early. That was our mojo, and that is how Linux became the dominant operating system it is today. Do we, the Linux community, still have that mojo? Regards, Daniel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/