Re: New Linux xfs/reiser file systems

> > Yes, this double-writing is a problem.  Suppose you have your WAL on a
> > separate drive.  You can fsync() WAL with zero head movement.  With a
> > log based file system, you need two head movements, so you have gone
> > from zero movements to two.
> 
> It may be worse depending on how the filesystem actually does
> journalling.  I wonder if an fsync() may cause ALL pending
> meta-data to be updated (even metadata not related to the 
> postgresql files).
> 
> Do you know if reiser or xfs have this problem?

I don't know, but the Linux user reported xfs was really slow.

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