Cygwin Filesystem Performance degradation 1.7.5 vs 1.7.7, and methods for improving performance

Corinna Vinschen
Thu Oct 7 16:10:00 GMT 2010

On Oct  7 17:38, Derry Shribman wrote:
> Hi,
> >> If so, what is needed is that lstat() will do QIF/QDF() for local
> >> shares, and QAF() for network shares.
> >
> > That doesn't help.  It might be a help for outmoded systems like XP, but
> > it doesn't differ from QIF on Vista and later.  Even for network drives,
> > from procmon on W7:
> > [...]
> > Note especially that the file gets opened for FILE_READ_ATTRIBUTES
> > access only, so this case doesn't differ from what Cygwin does anyway.
> >
> > It also does not matter whether the drive is mounted via a drive letter
> > or if the call uses an UNC path.  I don't see that this special case has
> > any future.
> Hmmm... very strange behavior of CIFS!

I found some vague hint on the internet which describes this problem and
connects it to UAC.  However, in contrast to the article on the net, I
could not reproduce a working FAST_IO by switching off UAC and rebooting
the machine.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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