Re: Linux 2.6.29

From: Linus Torvalds
Date: Sun Mar 29 2009 - 11:52:39 EST




On Sun, 29 Mar 2009, Pavel Machek wrote:
>
> Actually ext2 is more reliable in ext3 -- fsck tells you
> about errors on parts of disk that are not normallly used.

No. ext2 is not more reliable than ext3.

ext2 gets way more errors (that whole 5s + 30s thing), and has no
"data=ordered" mode to even ask for more reliable behavior.

And even if compared to "data=writeback" (which approximates the ext2
writeout ordering), and assuming that the errors are comparable, at least
ext3 ends up automatically fixing up a lot of the errors that cause
inabilities to boot etc.

So don't be silly. ext3 is way more reliable than ext2. In fact, ext3 with
"data=ordered" is rather hard to screw up (but not impossible), and the
only real complaint in this thread is just the fsync performance issue,
not the reliability.

So don't go overboard. Ext3 works perfectly well, and has just that one
(admittedly fairly annoying) major issue - and one that wasn't really
historically even a big deal. I mean, nobody really did fsync() all that
much, and traditionally people cared more about throughput than latency
(or at least that was what all the benchmarks are about, which sadly seems
to still continue).

I do agree that "data=writeback" is broken, but ext2 was equally broken.

Linus
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