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Re: reiserfs empirical study (very long)

I thought I read somewhere that XFS is working on PPC..
I take it that info was incorrect?


On Wed, 30 May 2001, Andrew Sharp wrote:

> Anton Blanchard wrote:
> > 
> > Me 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.
> > 
> > Sane architectures (sparc64, ppc) have load/store with byte swap
> > instructions and if reiserfs is using them you shouldnt see a
> > performance penalty.
> > 
> > cpu_to_le* etc make use of them.
> It does use them, but are these functions inlines with just one
> instruction?  If not, then there is a penalty.  These handy
> instructions just make that penalty a little less painful.
> People have already mentioned enough cases here to convince me that
> they do need to be moveable.  The one truly convincing case is
> wanting to have reiserfs be the root file system, but the hardware
> only allows one disk at a time.  One could be a hardass and say
> yeah, just do it on a similar machine, but my coffee is kicking in
> so I don't need to be a hardass anymore today.
> I guess this is just another case where we suffer a small bite
> because we're different from x86.  Sometime you bite the bear,
> however.  Someone said that XFS is stored bigendian.  Which will be
> great when it works on PowerPC/SPARC ~:^)
> a
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