Re: Linux 2.6.29

Gene Heskett
2009-03-27T19:19:46Z

On Friday 27 March 2009, Theodore Tso wrote:
>On Fri, Mar 27, 2009 at 11:05:58AM -0700, Linus Torvalds wrote:
>> Alan. Repeat after me: "fsync()+close() is basically useless for any app
>> that expects user interaction under load".
>>
>> That's a FACT, not an opinion.
>
>This is a fact for ext3 with data=ordered mode. Which is the default
>and dominant filesystem today, yes. But it's not true for most other
>filesystems. Hopefully at some point we will migrate people off of
>ext3 to something better. Ext4 is available today, and is much better
>at this than ext4. In the long run, btrfs will be better yet. The
>issue then is how do we transition people away from making assumptions
>that were essentially only true for ext3's data=ordered mode. Ext4,
>btrfs, XFS, all will have the property that if you fsync() a small
>file, it will be fast, and it won't inflict major delays for other
>programs running on the same system.
>
>You've said for a long that that ext3 is really bad in that it
>inflicts this --- I agree with you. People should use other
>filesystems which are better. This includes ext4, which is completely
>format compatible with ext3. They don't even have to switch on
>extents support to get better behaviour. Just mounting an ext3
>filesystem with ext4 will result in better behaviour.

Ohkay. But in a 'make xconfig' of 2.6.28.9, how much of ext4 can be turned on
without rendering the old ext3 fstab defaults incompatible should I be forced
to boot a kernel with no ext4 support?

--
Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Never look a gift horse in the mouth.
-- Saint Jerome