[PATCH] Set FILE_ATTRIBUTE_TEMPORARY on files opened by mkstemp() on WinNT
Fri Jul 22 18:28:00 GMT 2005
On Fri, Jul 22, 2005 at 12:28:08PM +0200, Vaclav Haisman wrote:
>On Thu, 21 Jul 2005, Christopher Faylor wrote:
>>On Fri, Jul 22, 2005 at 03:17:33AM +0200, Vaclav Haisman wrote:
>>>On Thu, 21 Jul 2005, Christopher Faylor wrote:
>>>>On Fri, Jul 22, 2005 at 01:32:50AM +0200, Vaclav Haisman wrote:
>>>>>the attached patch sets FILE_ATTRIBUTE_TEMPORARY on files opened by
>>>>>mkstemp() on WinNT class systems. Theoretically the OS should then be
>>>>>less eager to write such files onto the physical storage and use cache
>>>>Thank you for the patch but unless you can demonstrate some obvious
>>>>performance improvements I don't think we'll be applying it. You've
>>>>slowed down (slightly) the common case of calling open for the uncommon
>>>>case of calling mk?temp.
>>>I am not sure what kind of slow down do you mean. Is it the one extra
>>It was more than one extra call, but yes.
>>>In that case the attached modified patch should fix it. The call to
>>>open_with_attributes() in open() gets inlined, I have checked the
>>>resulting .s file.
>>Can you demonstrate some obvious performance improvements? Does it
>>speed up configure, make bash start up faster, make the rxvt window
>>faster to show up?
>I don't think that any of the extra ifs and assignments could cause any
>measurable slowdown. I also do not think that there are any _obvious_
>speed ups. It is merely a hint to the cache subsystem, not a silver
I wasn't asking if there was a slowdown. I wanted to know the rationale
for this change. Increasing code complexity for no obvious gain is not
something that I want to do.
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