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From: Brian Inglis <Brian DOT Inglis AT SystematicSW DOT Invalid>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: DREADED fseek
Organization: Systematic Software
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Date: Wed, 29 Dec 2004 00:41:02 GMT
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To: djgpp AT delorie DOT com
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On Tue, 28 Dec 2004 07:45:26 -0500 in comp.os.msdos.djgpp, DJ Delorie
<dj AT delorie DOT com> wrote:

>
>> The default appears to be about equivalent to setvbuf() with 12KB,
>> doing sequential reads on my machine and drive.
>
>Are you doing enough reads to make the initial buffer learning curve
>insignificant?  Or at least do a couple of reads before starting the
>timer?  Remember, it takes 3-4 freads before it's running at full
>speed.

I tested a bunch of ~20MB files, the largest I have on my machine,
timed from fopen() to fclose() in all cases, and ignored the first run
loading the cache. 
Is there any documented common interface to bypass/disable/reenable a
cache under DOS/Windows, so I can get raw I/O speeds? 

-- 
Thanks. Take care, Brian Inglis 	Calgary, Alberta, Canada

Brian DOT Inglis AT CSi DOT com 	(Brian[dot]Inglis{at}SystematicSW[dot]ab[dot]ca)
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