From: Eric Sandeen Subject: Re: ext4 fallocate+truncate not freeing up allocated space Date: Sat, 30 Oct 2010 10:43:55 -0500 Message-ID: <4CCC3D3B.30205@redhat.com> References: <007a01cb7796$d515da50$7f418ef0$@com> <4CCB14D6.6070605@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: linux-ext4@vger.kernel.org To: George Kola Return-path: Received: from mx1.redhat.com ([209.132.183.28]:28997 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752618Ab0J3PoA (ORCPT ); Sat, 30 Oct 2010 11:44:00 -0400 In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: George Kola wrote: > Hi Erik, > Thanks for replying. How to get a hold of kernel 2.6.18-225.el5 ? It (or a later kernel) will be available to RHEL subscribers when released, and CentOS at some time after that, on their schedule. > I found 2.6.18-227 at http://people.redhat.com/jwilson/el5/227.el5/x86_64/ > I tried it and the bug is fixed is 2.6.18-227. Thanks for your help. > > This may be off-topic -- how do I find the changes from 2.6.18-194.17.4 > to 2.6.18-225 (or 2.6.18-227) ? I just want to know what other changes I > am installing in addition to the bug fix. The kernel RPM changelog has a general description of changes, usually with reference to bug numbers. -Eric > > Thanks, > George > > > On Fri, Oct 29, 2010 at 11:39 AM, Eric Sandeen > wrote: > > George Kola wrote: > > I am using RHEL (CentOS) 5.5 with kernel 2.6.18-194.17.4.el5 and > ext4. I > > posted to RHEL bugzilla and they requested me to post it here. > > > > ... > > > Steps to Reproduce: > > Have a program > > 1. Open a file on ext4 partition > > # touch testfile > > > 2. Fallocate space for that file say 20 GB > > # /root/fallocate -l 20g testfile > # df -h . > Filesystem Size Used Avail Use% Mounted on > /dev/sdb2 30G 21G 7.7G 73% /mnt/test > # du -h testfile > 21G testfile > > > 3. Write data to the file (but less than the allocated space) say > 10 GB > > # dd if=/dev/zero of=testfile bs=10M count=1024 conv=notrunc > 10737418240 bytes (11 GB) copied, 125.522 seconds, 85.5 MB/s > # du -h testfile > 21G testfile > # df -h . > Filesystem Size Used Avail Use% Mounted on > /dev/sdb2 30G 21G 7.7G 73% /mnt/test > > > 4. Close the file > > 5. Call truncate(file-path, size+1), truncate(file-path,size) on > that file > > to > > give up the space (observed that the space is given up using filefrag) > > 10g size I assume? Is the below representative? > > # /root/truncate 10737418241 testfile > # ls -l testfile > -rw-r--r-- 1 root root 10737418241 Oct 29 13:48 testfile > # /root/truncate 10737418240 testfile > # ls -l testfile > -rw-r--r-- 1 root root 10737418240 Oct 29 13:48 testfile > > > 6. Use du and df on that ext4 partition to find that the mismatch > > # df -h . > Filesystem Size Used Avail Use% Mounted on > /dev/sdb2 30G 11G 18G 37% /mnt/test > > # du -h testfile > 11G testfile > > # uname -a > Linux bear-05 2.6.18-225.el5 #1 SMP Mon Sep 27 10:32:19 EDT 2010 > x86_64 x86_64 x86_64 GNU/Linux > > Seems to work here, though there are ext4 updates in that kernel. > > -Eric > > > > > > > -George > > > > > > > > -- > > To unsubscribe from this list: send the line "unsubscribe > linux-ext4" in > > the body of a message to majordomo@vger.kernel.org > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > >