From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?utf-8?B?SsO2cm4=?= Engel Subject: Re: [PATCH 1/3] fs: Document the reflink(2) system call. Date: Tue, 5 May 2009 18:54:33 +0200 Message-ID: <20090505165433.GB32180@logfs.org> References: <1241331303-23753-1-git-send-email-joel.becker@oracle.com> <1241331303-23753-2-git-send-email-joel.becker@oracle.com> <20090505010703.GA12731@shareable.org> <20090505071608.GB10258@mail.oracle.com> <20090505130114.GD17486@mit.edu> <20090505131907.GF25328@shareable.org> <1241530798.7244.65.camel@think.oraclecorp.com> <20090505153629.GB31100@shareable.org> <20090505164619.GA32180@logfs.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Chris Mason , Theodore Tso , linux-fsdevel@vger.kernel.org, jmorris@namei.org, ocfs2-devel@oss.oracle.com, viro@zeniv.linux.org.uk To: Jamie Lokier Return-path: Received: from lazybastard.de ([212.112.238.170]:57797 "EHLO longford.logfs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753290AbZEEQyo (ORCPT ); Tue, 5 May 2009 12:54:44 -0400 Content-Disposition: inline In-Reply-To: <20090505164619.GA32180@logfs.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Tue, 5 May 2009 18:46:19 +0200, J=C3=B6rn Engel wrote: >=20 > And depending on the fs design, the read/write loop can be > replaced with finer-grained reference counting. And maybe finer-grained reference counting should be a requirement for copyfile/cowlink/reflink or whatever we call it. With a large file on slow media, open("foo", O_RDWR); should still return in a reasonable amount of time. Not after ten minutes. J=C3=B6rn --=20 =46ancy algorithms are slow when n is small, and n is usually small. =46ancy algorithms have big constants. Until you know that n is frequently going to be big, don't get fancy. -- Rob Pike -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?utf-8?B?SsO2cm4=?= Engel Date: Tue, 5 May 2009 18:54:33 +0200 Subject: [Ocfs2-devel] [PATCH 1/3] fs: Document the reflink(2) system call. In-Reply-To: <20090505164619.GA32180@logfs.org> References: <1241331303-23753-1-git-send-email-joel.becker@oracle.com> <1241331303-23753-2-git-send-email-joel.becker@oracle.com> <20090505010703.GA12731@shareable.org> <20090505071608.GB10258@mail.oracle.com> <20090505130114.GD17486@mit.edu> <20090505131907.GF25328@shareable.org> <1241530798.7244.65.camel@think.oraclecorp.com> <20090505153629.GB31100@shareable.org> <20090505164619.GA32180@logfs.org> Message-ID: <20090505165433.GB32180@logfs.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Jamie Lokier Cc: Chris Mason , Theodore Tso , linux-fsdevel@vger.kernel.org, jmorris@namei.org, ocfs2-devel@oss.oracle.com, viro@zeniv.linux.org.uk On Tue, 5 May 2009 18:46:19 +0200, J?rn Engel wrote: > > And depending on the fs design, the read/write loop can be > replaced with finer-grained reference counting. And maybe finer-grained reference counting should be a requirement for copyfile/cowlink/reflink or whatever we call it. With a large file on slow media, open("foo", O_RDWR); should still return in a reasonable amount of time. Not after ten minutes. J?rn -- Fancy algorithms are slow when n is small, and n is usually small. Fancy algorithms have big constants. Until you know that n is frequently going to be big, don't get fancy. -- Rob Pike