Date: Mon, 1 Jul 1996 13:15:06 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Justin Ward <justin AT yoss DOT canweb DOT net>
Cc: djgpp AT delorie DOT com
Subject: Re: why have a ramdisk??
In-Reply-To: <Pine.BSF.3.91.960630161653.18189A-100000@yoss.canweb.net>
Message-Id: <Pine.SUN.3.91.960701130507.17336A-100000@is>
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Content-Type: TEXT/PLAIN; charset=US-ASCII


On Sun, 30 Jun 1996, Justin Ward wrote:

> Reading through the FAQ, it said that you should (if you have enough ram) 
> make a ramdisk and tell DJGPP to use that for swap space.

That's not what the FAQ says.  The FAQ says to point the "TMPDIR" 
environment variable to the RAM disk.  "TMPDIR" value is used by library
functions that create temporary files, not as the place to use as swap
space.  Temporary files are files that are deleted when the program exits;
e.g. the compiler passes invoked by the GCC driver use such files to
communicate between them.  As these files aren't needed after the program
terminates, it makes sense to put them into a RAM disk, to make I/O
faster. 

Swap space, on the other hand, MUST be on a physical disk, because it's 
only used when the physical RAM is exhausted.  The place where the swap 
space resides depends entirely on the DPMI server you use, DJGPP programs 
has no means of telling the server where to put it.  For example, if you 
run under Windows, the Windows swap file serves as swap space, and no 
program can change that without restarting Windows.