hi i got 2 questions and maybe someone could shed some light: a) i'm using kernel 2.4.17 and use ext3 in it. is it possible that the whole system is slower than with ext2? i switched back to ext2 (great feature!!!) and the system's response seemed somewhat better. should/could there be such a effect as double writing of journaled data? i didnt activate debugging (jbd). b) is reiserfs compatible with ext3? is it possible use both journaling filesystems at the same time (of course on different partitions :)) i think i remember some talks about namespace-collisions. yours josef
hi i got 2 questions and maybe someone could shed some light: a) i'm using kernel 2.4.17 and use ext3 in it. is it possible that the whole system is slower than with ext2? i switched back to ext2 (great feature!!!) and the system's response seemed somewhat better. should/could there be such a effect as double writing of journaled data? i didnt activate debugging (jbd). b) is reiserfs compatible with ext3? is it possible use both journaling filesystems at the same time (of course on different partitions :)) i think i remember some talks about namespace-collisions. yours josef
On Mon, Feb 04, 2002 at 11:28:11AM +0100, Joe Radinger wrote:> hi > i got 2 questions and maybe someone could shed some light: > > a) i'm using kernel 2.4.17 and use ext3 in it. is it possible that the > whole system is slower than with ext2? i switched back to ext2 (great > feature!!!) and the system's response seemed somewhat better. > should/could there be such a effect as double writing of journaled data?It kind of depends on your hardware and disk usage. In many cases, however, ext3 has higher performance because it can serialize operations.> i didnt activate debugging (jbd). > > b) is reiserfs compatible with ext3?You can have it compiled into the same kernel and run it on the same computer as ext3, if that's what you mean.> is it possible use both journaling filesystems at the same time (of > course on different partitions :))Yes. I'm doing that right now, in addition to using XFS for source libraries and JFS for temporary stuff.> i think i remember some talks about namespace-collisions.I don't recall anything like that. I've been using both ext3 and ReiserFS since the 2.4.5 kernel. Maybe it was before that? -- -- Skylar Thompson (skylar@attglobal.net)
On Mon, Feb 04, 2002 at 11:28:11AM +0100, Joe Radinger wrote:> a) i'm using kernel 2.4.17 and use ext3 in it. is it possible that the > whole system is slower than with ext2? i switched back to ext2 (great > feature!!!) and the system's response seemed somewhat better. > should/could there be such a effect as double writing of journaled data?Depends on what you do. FOr certain applications, ext3 can be faster than ext2> b) is reiserfs compatible with ext3?No.> is it possible use both journaling filesystems at the same time (of > course on different partitions :))Yes. -- Ralf Hildebrandt (Im Auftrag des Referat V A) Ralf.Hildebrandt@charite.de Charite Campus Virchow-Klinikum Tel. +49 (0)30-450 570-155 Referat V A - Kommunikationsnetze - Fax. +49 (0)30-450 570-916 A distributed system is one in which the failure of a computer you didn't even know existed can render your own computer unusable.
Hi, On Mon, Feb 04, 2002 at 11:28:11AM +0100, Joe Radinger wrote:> i got 2 questions and maybe someone could shed some light: > > a) i'm using kernel 2.4.17 and use ext3 in it. is it possible that the > whole system is slower than with ext2? i switched back to ext2 (great > feature!!!) and the system's response seemed somewhat better.ext3 does often submit IO in bursts (because of the journal writes), and that seems to have a big impact if the VM is not working well. 2.4.17 has about the worst VM available for current kernels. Could you try again, either with Rik's rmap patches, or Andrea's current aa diffs? Both of those fix the many incompletenesses of the main 2.4.17 VM.> should/could there be such a effect as double writing of journaled data?No, but metadata will always be written twice in a physically journaling filesystem such as ext3 or reiserfs.> b) is reiserfs compatible with ext3?You can use both at the same time, yes, but reiserfs has a different on-disk format to ext3 so you have to chose one or the other for a given filesystem.> is it possible use both journaling filesystems at the same time (of > course on different partitions :))Yes. Cheers, Stephen
Would 2.4.17 patched to 2.4.18-pre6 be better or worse than stock 2.4.17 ? a not-related question: what progress is being made on merging Daniel Phillip's "htree" into main Linux kernel ? Thanks for any and all information, -Mike Slifcak, working for Guardent, Inc.> -----Original Message----- > From: Stephen C. Tweedie [mailto:sct@redhat.com] > Sent: Monday, February 04, 2002 11:36 AM > To: Joe Radinger > Cc: ext3-users@redhat.com > Subject: Re: slowdown and reiserfs > > > Hi, > > On Mon, Feb 04, 2002 at 11:28:11AM +0100, Joe Radinger wrote: > > > i got 2 questions and maybe someone could shed some light: > > > > a) i'm using kernel 2.4.17 and use ext3 in it. is it > possible that the > > whole system is slower than with ext2? i switched back to > ext2 (great > > feature!!!) and the system's response seemed somewhat better. > > ext3 does often submit IO in bursts (because of the journal writes), > and that seems to have a big impact if the VM is not working well. > 2.4.17 has about the worst VM available for current kernels. Could > you try again, either with Rik's rmap patches, or Andrea's current aa > diffs? Both of those fix the many incompletenesses of the main 2.4.17 > VM. > > > should/could there be such a effect as double writing of > journaled data? > > No, but metadata will always be written twice in a physically > journaling filesystem such as ext3 or reiserfs. > > > b) is reiserfs compatible with ext3? > > You can use both at the same time, yes, but reiserfs has a different > on-disk format to ext3 so you have to chose one or the other for a > given filesystem. > > > is it possible use both journaling filesystems at the same time (of > > course on different partitions :)) > > Yes. > > Cheers, > Stephen > > > >