On 04/26/2013 06:50 AM, Romain Francoise wrote:
> there are still many situations where it does help get the data to
> disk in time to prevent data loss

I'm sympathetic to this comment.  Still, Emacs uses fsync
far too often, and this often significantly hurts performance
for no particularly good reason.

How about the attached patch instead?  It causes Emacs to use fsync by
default only when operating interactively.  When running in batch
mode, fsync is disabled by default.  This would fix the performance
problem I observed (Emacs batch byte-compiles) without affecting
the warm fuzzy feeling one gets when one types C-x C-s.

I suppose Stefan may prefer the original patch, as it's simpler.
I'm OK either way, I guess.