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Re: reiserfs empirical study (very long)

Andrew Sharp wrote:
> Geert Uytterhoeven wrote:
> >
> > On Wed, 30 May 2001, Andrew Sharp wrote:
> > > The big endian patches change the code to use little endian ordering
> > > for all on-disk structures.  IMO this is a mistake, and certainly
> > > costs a dear performance penalty, because on big endian processors,
> > > this method requires converting endianness both ways (reading and
> > > writing) for all meta data.  I submit that there is little reason
> > > for this, and the performance cost is not worth the very dubious
> > > feature of having the file system be moveable to little endian
> > > systems, like x86.  Note that except in few cases, the disk labels
> >
> > We had the same discussion many years ago about ext2fs, and a few years
> > later about XFS. In fact m68k and ppc used to have a big-endian ext2fs.
> >
> > Now ext2fs is defined to store metadata in little-endian order, and XFS to
> > store metadata in big-endian order. This was done for interoperability
> > reasons.
> >
> > Since people do want to exchange disks between machines, the alternative
> > was to support both endiannesses. In fact m68k did have a bi-endian ext2fs
> > for a
> I would actually like to hear more about these discussions.  Are
> there any archives?  Are they too old?  Geez, if some silly person
> wants to take a disk from one machine to another, well, that is what
> vfat is for, no?  ~:^)

You are way off. If the endianness of reiserfs wasn't defined, I couldn't be
running it now. Because I can only connect one disk to this PowerBook, so I
had to partition the new one in my Athlon box (parted rules :), mkreiserfs
there and then move my filesystem over with tar via ssh (and MacOS with cat
via ssh ;).

Earthling Michel Dänzer (MrCooper)    \   Debian GNU/Linux (powerpc) developer
CS student, Free Software enthusiast   \        XFree86 and DRI project member

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