From: "John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: DJ: Compiler Optimizations
Date: Fri, 20 Mar 1998 21:56:17 -0500
Organization: Two pounds of chaos and a pinch of salt.
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James W Sager Iii wrote:
> 
> I just read through the FAQ.
> I set up my smartdrive better so my system dies less on me.
> Also I noted I could set up a ram-drive.  I did set this
> 12 meg ramdrive up, and set the temp variable equal to it, but I
> noticed no marked performance gain.  To get the incrdible speed of
> the ramdrive, what settings should I set in rhide?  Or should
> I copy over some files to the ramdrive each time I want to use DJ?
> Any help is appreciated, I'm just tired of waiting a minute and a half
> for my programs to compile on DJ when TC only takes 10 seconds.

Here are some general pieces of advice.  They may not apply equally to
you and your system; in other words, YMMV:

 - Make sure that the environment variable TMPDIR is what you have set
to point to the RAM drive.  TEMP, TMP, etc., won't work.
 - Make sure your SMARTDRV cache is set to buffer both reads and writes.
 - As long as your RAM drive is large enough to hold all of gcc's
temporary files, excess space goes to waste.
 - On the other hand, the larger your SMARTDRV cache, the better.
 - SMARTDRV running in plain DOS is not as efficient as Windows 95's
disk cache.  In fact, running from a DOS box under Win95 can double or
triple compilation speeds.
 - Make sure your caches aren't so big that they leave too little memory
left for gcc to run in!  Typing 'go32-v2' at the DOS prompt can tell you
if you have memory problems.

Even with all these tips, your compilation speed with DJGPP is likely to
be slower than with an IDE-based compiler because of the time required
to load the individual executables.  Also, keep in mind that Turbo C is
an obsolete 16-bit compiler.  It performs quite a bit less work when it
compiles programs than gcc does.  Those extra CPU cycles result in much
higher-quality code.

-- 
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