On Thu, 2002-04-18 at 14:50, Richard Troy wrote: > > cry for "performance." My rethort was, "Yeah, some performance while > you're rebuilding your system from tape! Hah!" :-) > So, I think it'd be really neat if someone would put together a small > table outlining what's available for our beloved RedHat Linux > systems, telling us whether or not they're included with Red Hat, or > whether we have to hunt down the RPMS, etc., and perhaps with a brief > statement of the technology and good applications. What I'm thinking of I think i already did that. But anyway... These are the journalised FSs that i know: 1. Ext3 Its main advantage is the easy upgrade from Ext2. Now, if you're like me and never upgrade but, instead, reinstall from scratch, this advantage looses much appeal. Nevertheless, it's good because "it's like ext2", people are familiar with it, there's a good chance that applications will work well with it (because they are already working well with Ext2)... When you're interested in the safety of the data, not only metadata, use it with data=journal. (but i can only think of databases in this case, and databases work actually better on raw disks) Performance-wise, there's a strange situation with some mail servers, when the performance on Ext3 with data=journal is actually very high! It has to do something with the order of the sync writes. It's available in the "official" RH distribution. 2. ReiserFS It is supposed to have a very high performance with lots of small files being created and deleted all the time, and that makes it ideal for proxy servers (Squid). It's fairly recent, and i had some stability problems with it one year ago, especially under heavy load and lots of disk I/O. But things might have been improved meanwhile. I guess there are more interesting things coming from ReiserFS in the future. It looks like its going to be a very featureful and clever FS (it tries to blur the difference between the FS and a database, and other nifty tricks). The "official" RH kernels do have ReiserFS support, but suboptimal: debug is turned on. I guess you can find modified kits/installers/kernels on the Net if you search them. I think some brasilian guys used to offer a ReiserFS-enabled RH... 3. XFS This is interesting, because the XFS code base is actually very mature and stable. That's why, i guess, the Linux port became stable so quickly: because only the Linux "hooks" had to be made stable, while the core was already mature. >From my experience (and from what i've been told by other people trying to solve similar problems), this is the FS that offers the best stability under extreme loads (in terms of CPU and I/O), especially for fileservers, or for (concurrent) access to very large files, or when you need "guaranteed" disk I/O bandwidth. Actually, it was designed to be like that: SGI needed those features for its 512 CPU video-processing machines. ;-) You can do Posix ACLs with it, and Samba takes advantage of that, translating them into Windows "ACLs". Quota also works. It also has extended attributes that enable you to store customised extra file information at the FS level (think of BeOS filesystem). Previous releases (up to 1.0.2) were slow when it comes to deleting lots of files, because all deletes were synchronous; this thing made it somewhat unappropriate for proxy servers and mail relays. The latest stable release (1.1) fixes that (although some people still believe sync deletes are "the right way" ;-)). You can get an XFS-enabled RH installer from here: http://oss.sgi.com/projects/xfs/ -- Florin Andrei There's nothing to be ashamed of in coming up with the obvious, especially when nobody else is coming up with it.
