From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pat LaVarre Subject: Re: srfs - a new file system. Date: 24 Oct 2003 14:52:44 -0600 Sender: linux-fsdevel-owner@vger.kernel.org Message-ID: <1067028764.16779.13.camel@patehci2> References: <20031024143829.GB11277@delft.aura.cs.cmu.edu> <20031024141146.O17778@schatzie.adilger.int> <1067027088.16779.4.camel@patehci2> <20031024143802.P17778@schatzie.adilger.int> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: tzachar@cs.bgu.ac.il, jaharkes@cs.cmu.edu, bulb@ucw.cz, linux-fsdevel@vger.kernel.org Return-path: Received: from email-out2.iomega.com ([147.178.1.83]:34809 "EHLO email.iomega.com") by vger.kernel.org with ESMTP id S262603AbTJXUxF (ORCPT ); Fri, 24 Oct 2003 16:53:05 -0400 To: adilger@clusterfs.com In-Reply-To: <20031024143802.P17778@schatzie.adilger.int> List-Id: linux-fsdevel.vger.kernel.org > There are lots of ways to read back garbage from a disk unrelated to > physical HDD errors: memory errors, bad cables, software errors (driver, > fs, vm, etc), bad IDE DMA settings, power failures during write, etc... Yes, thank you for finding words to express that fact so much more clearly than I did. > There are lots of ways to read back garbage from a disk unrelated to > physical HDD errors: memory errors, bad cables, software errors (driver, > fs, vm, etc), bad IDE DMA settings, power failures during write, etc... In particular, I see HDD's vary in their opinion of which cabling and configuration and protocol is bad. Therefore I ask: "How can we know how commonly that occurs in practice, so that we can know how often we're wrong to believe such things as our locally recorded vector time?" Is there, as yet, no linux filesystem that preserves the integrity of the data and metadata despite such failures? If I could write such an fs on to a single directly-attached local drive, then I could measure how often I myself experience such failures. I'm confident I actually do experience these failures because often I work in comparative, raid-like measures. When I see one drive and another disagree about what I wrote, then whenever I trust my write and diff and read tools I must conclude one or both of the HDD's is wrong. Pat LaVarre