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Date: Thu, 2 Jun 2005 13:02:30 -0400 (EDT)
From: Igor Pechtchanski <pechtcha AT cs DOT nyu DOT edu>
Reply-To: cygwin AT cygwin DOT com
To: Linda W <cygwin AT tlinx DOT org>
cc: cygwin AT cygwin DOT com
Subject: Re: Serious performance problems (malloc related?)
In-Reply-To: <429ED094.9080001@tlinx.org>
Message-ID: <Pine.GSO.4.61.0506021301320.10282@slinky.cs.nyu.edu>
References: <4297A14B DOT 9070409 AT plausible DOT org> <20050528131501 DOT V53507 AT logout DOT sh DOT cvut DOT cz>  <20050528160424 DOT GB12395 AT trixie DOT casa DOT cgf DOT cx> <429ED094 DOT 9080001 AT tlinx DOT org>
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On Thu, 2 Jun 2005, Linda W wrote:

> In tracing the Win32 file operations, find seems to perform multiple
> file open operations for each file processed.  One way to speed up
> operations in this area might be to keep a "cache" of the last "N"
> file handles.  I suspect it's just the Windows path lookup mechanism
> being slow to reopen things.  But if the cygwin.dll could cache even
> the past 5 entries, it might speed things up significantly.  If it
> is opened each time to read different information, it might be much
> cheaper to collect all the information at one time and cache it in
> an internal "inode cache" that could expire in a second or so.
> If it would "slow" down other programs, it could have some smarts in
> the system calls to look for calling patterns from programs like find
> that need a couple or more openings to fully "process a file", that all
> happen within a few milliseconds of each other.

<http://cygwin.com/acronyms/#SHTDI>.  <http://cygwin.com/acronyms/#PTC>.
	Igor
-- 
				http://cs.nyu.edu/~pechtcha/
      |\      _,,,---,,_		pechtcha AT cs DOT nyu DOT edu
ZZZzz /,`.-'`'    -.  ;-;;,_		igor AT watson DOT ibm DOT com
     |,4-  ) )-,_. ,\ (  `'-'		Igor Pechtchanski, Ph.D.
    '---''(_/--'  `-'\_) fL	a.k.a JaguaR-R-R-r-r-r-.-.-.  Meow!

"The Sun will pass between the Earth and the Moon tonight for a total
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