[PATCH] Add man page for vfs_syncops

[Volker Lendecke]

On Fri, Aug 09, 2013 at 02:12:46AM -0700, Christoph Hellwig wrote:
> On Fri, Aug 09, 2013 at 11:08:03AM +0200, Karolin Seeger wrote:
> > +	Some filesystems (even some journaled filesystems) require that a
> > +	fsync() be performed on many meta data operations to ensure that the
> > +	operation is guaranteed to remain in the filesystem after a power
> > +	failure. This is particularly important for some cluster filesystems
> > +	which are participating in a node failover system with clustered
> > +	Samba. On those filesystems the <command>vfs_syncops</command> VFS module
> > +	provides a way to perform those	operations safely.
> 
> I don't know a single Unix filesystems from the last 40 years where this
> is not true.  Why isn't this the default behaviour in Samba instead of
> having it in a module that very few people are going to use?

Performance. fsync is very expensive in many situations.

Volker

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