Re: Ext3 vs NTFS performance

Theodore Tso
2007-05-02T19:29:06Z

On Wed, May 02, 2007 at 08:40:35PM +0200, Andi Kleen wrote:
> Theodore Tso <tytso@mit.edu> writes:
>
> > On Wed, May 02, 2007 at 02:21:40PM +0200, Andi Kleen wrote:
> > > Andrew Morton <akpm@linux-foundation.org> writes:
> > > >
> > > > Conceivably we could address this in the filesystem without mucking other
> > > > things up. But I'd have thought the simplest damage-control would be to
> > > > detect this pattern in samba and to then use glibc's fallocate().
> > >
> > > The advantage of detecting it in kernel would be that it would handle
> > > Linux applications that do this (I suspect there are some) too.
> >
> > Um, which applications do you suspect? So we can hunt down those user
> > space applications programmers and slap them silly? Or rather,
> > unsilly, since that there's no good reason to ever suspect that
> > writing a byte every 128k would result in a good allocation layout on disk?
>
> Anything that uses glibc fallocate() ?

Glibc's fallocate current writes all zeros, not 1 byte every
128kbytes. And once we wire up the new sys_fallocate() support, we'll
have the right preallocation support in ext4.

- Ted