Re: [RFC/PATCH v2 1/1] cygwin: Add fast_lstat() and fast_fstat() functions

On 07/15/2013 03:49 PM, Junio C Hamano wrote:

Mark Levedahl [off-list ref] writes:

quoted

quoted

In order to limit the adverse effects caused by this implementation,
we provide a new "fast stat" interface, which allows us to use this
only for interactions with the index (i.e. the cached stat data).

Signed-off-by: Ramsay Jones <redacted>
---

I've tested this on Cygwin 1.7 on WIndows 7 , comparing to the results
using your prior patch (removing the Cygwin specific lstat entirely)
and get the same results with both, so this seems ok from me.

My comparison point was created by reverting your current patch from
pu, then reapplying your earlier patch on top, so the only difference
was which approach was used to address the stat functions.

Caveats:
1) I don't find any speed improvement of the current patch over the
previous one (the tests actually ran faster with the earlier patch,
though the difference was less than 1%).
2) I still question this whole approach, especially having this
non-POSIX compliant mode be the default. Running in this mode breaks
interoperability with Linux, but providing a Linux environment is the
*primary* goal of Cygwin.

Sounds like we are better off without this patch, and instead remove
the "schizophrenic stat"?  I do not have a strong opinion either
way, except that I tend to agree with your point 2) above.

In case my opinion is unclear, I think removal of the schizophrenic stat 
is the right approach. Speed is important, but not at the expense of 
correctness.

Mark