On Thu, 2007-12-20 at 22:17 +0100, Mario Vukelic wrote: > When ext3 was new, I am pretty certain that I have read quotes by > Theodore T'so that he does not recommend turning off the checks. It's > been a long time though, and searching now turns up nothing definitive > for me.
Ah, I think I found an incomplete quote of what I had in mind. It's not really conclusive, and I'd like to know that was edited out anyway. http://batleth.sapienti-sat.org/projects/FAQs/ext3-faq.html "Q: If a system shutdown hard, even with journaling is it at all necessary to run e2fsck? Theodore Ts'o said: It's best to just always run e2fsck. [...] E2fsck will run the journal automatically, and if the filesystem is otherwise clean, it skip doing a full filesystem check. If the filesystem is not clean (because during the previous run the kernel noticed some filesystem inconsistencies), e2fsck will automatically do a full check if it is necessary. If you have multiple disks, fsck will run multiple e2fsck processes in parallel, thus speeding up your boot sequence than if you let the kernel replay the journal for each filesystem when it tries to mount it, since then the journal replays will be done sequentially, instead of in parallel." Here's Stephen Tweedie, he clearly states that no fsck is needed after a dirty unmount, but I don't find anything on periodic scheduled checks (which can be scheduled only on a server, not a personal computer). Is Tweedie still at RedHat? If so it should be no problem to ask. http://olstrans.sourceforge.net/release/OLS2000-ext3/OLS2000-ext3.html "And some of these EXT2 filesystems are getting really rather big. Even 24 months ago, there were people building 500 gigabyte EXT2 filesystems. They take a long time to fsck. I mean, really. These are filesystems that can take three or four hours just to mkfs. Doing a consistency check on them is a serious down time. So the real objective in EXT3 was this simple thing: availability. When something goes down in EXT3, we don't want to have to go through a fsck. We want to be able to reboot the machine instantly and have everything nice and consistent. And that's all it does. It's a minimal extension to the existing EXT2 filesystem to add journaling. And it's really important, EXT2 is the workhorse filesystem. It's the standard stable filesystem. We don't want to turn EXT2 into an experimental filesystem. For one thing, users expect to have EXT2 there as a demonstration of how to code filesystems for Linux. It's a small, easily understood filesystem which demonstrates how to do all of the talking to the page cache, which has changed in 2.4, all of the locking in the directory handling, which has changed in 2.4. All of these changes in the VFS interface and the VM interface that filesystems have to deal with are showcased in EXT2. So there are multiple reasons why we really do not want to start making EXT2 into an experimental filesystem, adding all sorts of new destabilizing features. And so the real goal for EXT3 was to provide the minimal changes necessary to provide a complete journaling solution. [03m, 26s] So it provides scaling of the disk filesystem size and it allows you to make larger and larger filesystems without the fsck penalty." -- Ubuntu-devel-discuss mailing list Ubuntu-devel-discuss@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel-discuss
