Subject: Re: LFS (was Thank you NetBSD)
To: Michael <>
From: Dieter <>
List: netbsd-users
Date: 02/25/2005 11:04:24
> >> If one is forced to run Linux :-( which FS is the least likely
> >> to lose data, and how much worse is it than NetBSD's FFS?

> > I've know people who have had systems with ext2 and ext3 crash, and 
> > lose
> > large amounts of data. I had a Slackware 10 system here for awhile, 
> > and used
> > reiserfs, which seemed fairly fast, but I never had a crash. I would 
> > bet JFS
> > and XFS are good based on my experience with AIX and IRIX.
> I'd pick jfs too - also based on AIX experience :)
> My site is hosted on a Motorola PowerStack II running AIX 4.3.2 for 
> ages, had several power outages - never lost a single byte of data and 
> it was always back online less than a minute after power was back. 
> ReiserFS has a reputation for trouble, but that's more or less SuSE's 
> fault and it may have changed. I can't really comment on XFS, I know it 
> from IRIX on an Indigo2 but I didn't play with it long enough to form a 
> reasonable opinion. It never made trouble, but that's what I'd expect 
> from any filesystem.
> If you want I can post bonnie++ results for a bunch of roughly 
> comparable machines ( S900 with 300MHz G3 under NetBSD, PowerStack II 
> with 300MHz 604e / AIX, Sun Ultra 10 with 333MHs UltraSPARC II / NetBSD 
> ... ) but they'd hardly be fair - different disks, different SCSI 
> hardware and so on. FFS has an edge when creating/deleting files, 
> thanks to softdeps, other tests show a slight edge for jfs. The AIX box 
> also manages higher throughput but it has Wide-SCSI while the S900 has 
> only narrow, the Sun has UW SCSI but slower disks so it's slowest. Both 
> the AIX box and the S900 have Seagate Barracuda SCA drives, raw speed 
> is sort of comparable but the AIX box has a nearly full 50GB drive, the 
> S900 a half-empty 9GB so the results wouldn't be really comparable 
> either.
> JFS on AIX seems to have slightly more overhead than FFS on NetBSD, 
> this may be related to the Logical Volume Manage. In everyday work 
> there's hardly a noticeable difference, NetBSD seems a tad more 
> responsive under high IO load though.

I'm not so worried about which FS has slightly more or less overhead,
in either time or space, or slightly more speed.

	Writing 1 to ~3 streams of 2.5 MB/s to disk. (linear, not
		random access)

	Reading 1 stream from disk (2.5 MB/s up to maybe 25 MB/s if
		nothing maxes out).  (mostly linear, some seeking
		but not really random access)

	Works well with large files ( 5 GB up to say 30-35 GB / file).

	Not lose data.

	Fsck doesn't take a year to run, and hopefully doesn't
		need manual intervention.

	Given the amount of data, disks will most likely be SATA
	rather than SCSI.

	Currently leaning towards RAID 1.