From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Al Boldi" Subject: RE: reiser4 plugins Date: Tue, 28 Jun 2005 09:37:24 +0300 Message-ID: <200506280637.JAA07320@raad.intranet> References: <42C05F16.5000804@xfs.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Return-path: To: In-Reply-To: <42C05F16.5000804@xfs.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Hans Reiser wrote: > Steve, there is a remark about XFS below which you are going to be > more expert on. > > Theodore Ts'o wrote: > >> >>XFS has similar issues where it assumes that hardware has powerfail >>interrupts, and that the OS can use said powerfail interrupt to stop >>DMA's in its tracks on an power failure, so that you don't have >>garbage written to key filesystem data structures when the memory >>starts suffering from the dropping voltage on the power bus faster >>than the DMA engine or the disk drives. So XFS is a great filesystem >>--- but you'd better be running it on a UPS, or on a system which has >>power fail interrupts and an OS that knows what to do. Ext3, because >>it does physical block journalling, does not suffer from this problem. >>(Yes, Resierfs uses logical journalling as well, so it suffers from >>the same problem.) >> True now, not so around 2.4.20 when XFS was rock-solid. I think they tried to improve on performance and broke something. I wish they would fix that because it forced me back to ext3, as in consistency over performance any time.