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Re: High CPU usage on posix_fallocate call - CVS version
- From: Corinna Vinschen <corinna-cygwin at cygwin dot com>
- To: cygwin at cygwin dot com
- Date: Mon, 5 Nov 2007 12:22:53 +0100
- Subject: Re: High CPU usage on posix_fallocate call - CVS version
- References: <002601c81daa$157a1fb0$406e5f10$@com>
- Reply-to: cygwin at cygwin dot com
On Nov 2 17:42, Rob Bosch wrote:
> I found on MSDN that Windows has the capfilealloc function in all Windows OS
> versions. This function was designed to create a preallocated capture file
> of a specified size. It seems like this would accomplish what cygwin needs
> with the posix_fallocate function?
Not at all. Did you *read* what this method is about?
> -----Original Message-----
> From: Rob Bosch [mailto:XXXXXXXX@XXX.XXX]
Even though this is your own mail address, please:
http://cygwin.com/acronyms/#PCYMTNQREAIYR
http://cygwin.com/acronyms/#TOFU
> When my compiled version of rsync is using the posix_fallocate function I?m
> getting significant CPU usage. [...]
> getting 20%-25% CPU utilization during the posix_fallocate call. [...]
> It also takes 20 minutes for the file to be created using this call.
I can't reproduce this behaviour. I created a 40 Gigs file (haven't 77
Gigs left) on my XP box using the posix_fallocate function (which, btw.,
is basically just a single native NT call under the hood) and it takes
roughly a few milliseconds.
Did you look for http://cygwin.com/acronyms/#BLODA ?
http://cygwin.com/ml/cygwin-talk/2007-q4/msg00026.html
Corinna
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Corinna Vinschen Please, send mails regarding Cygwin to
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