[SCM] Samba Shared Repository - branch v3-0-test updated - release-3-0-32-11-g0b39c04

[Jeremy Allison]

On Thu, Sep 04, 2008 at 09:56:31AM -0700, Jeremy Allison wrote:
> On Thu, Sep 04, 2008 at 03:48:11PM +1000, tridge at samba.org wrote:
> > Hi Simo,
> > 
> >  > Please revert this change immediately. That change would slow down tdb
> >  > by a couple of orders or magnitude for our temporary databases.
> > 
> > actually this will only slow us down each time we attach/detach to the
> > tdb or we expand it (as expand uses munmap/mmap). I guess the question
> > is how often we expand our temporary tdb's.
> > 
> > A simple change would be for this not to apply if TDB_CLEAR_IF_FIRST
> > is set.
> 
> What about changing the MS_SYNC flag in the msync call to MS_ASYNC
> instead ? That would seem to have the desired effect in that it
> satifies the (seeming) requirement that msync be called before 
> munmap, but won't block until all writes are finished.

Hmmm. Nope. Checked the Linux source code and msync(MS_ASYNC)
is a no-op :-).

Jeremy.