From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladislav Bolkhovitin Subject: Re: [sqlite] light weight write barriers Date: Sat, 17 Nov 2012 00:02:44 -0500 Message-ID: <50A71A74.7040706@vlnb.net> References: <5086F5A7.9090406@vlnb.net> <20121025051445.GA9860@thunk.org> <508B3EED.2080003@vlnb.net> <20121027044456.GA2764@thunk.org> <5090532D.4050902@vlnb.net> <20121031095404.0ac18a4b@pyramind.ukuu.org.uk> <5092D90F.7020105@vlnb.net> <20121101212418.140e3a82@pyramind.ukuu.org.uk> <50931601.4060102@symas.com> <20121102123359.2479a7dc@pyramind.ukuu.org.uk> <50A1C15E.2080605@vlnb.net> <20121113174000.6457a68b@pyramind.ukuu.org.uk> <50A442AF.9020407@vlnb.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: General Discussion of SQLite Database , Theodore Ts'o , Richard Hipp , linux-kernel , linux-fsdevel@vger.kernel.org To: =?UTF-8?B?5p2o6IuP56uLIFlhbmcgU3UgTGk=?= Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org =E6=9D=A8=E8=8B=8F=E7=AB=8B Yang Su Li, on 11/15/2012 11:14 AM wrote: > 1. fsync actually does two things at the same time: ordering writes (= in a > barrier-like manner), and forcing cached writes to disk. This makes i= t very > difficult to implement fsync efficiently. Exactly! > However, logically they are two distinctive functionalities Exactly! Those two points are exactly why concept of barriers must be forgotten = for sake of=20 productivity and be replaced by a finer grained abstractions as well as= why they=20 where removed from the Linux kernel Vlad