Date: Mon, 03 Nov 1997 11:00:22 +1100
From: Bill Currie <billc AT blackmagic DOT tait DOT co DOT nz>
Subject: Re: FYI: speed of Allegro/DJGPP
In-reply-to: <Pine.SUN.3.91.971030173107.5238A-100000@is>
To: djgpp AT delorie DOT com
Message-id: <199711022157.KAA13126@teleng1.tait.co.nz gatekeeper.tait.co.nz>
Organization: Tait Electronics Limited
MIME-version: 1.0
Content-type: text/plain; charset=US-ASCII
Content-transfer-encoding: 7BIT
References: <3 DOT 0 DOT 16 DOT 19971030165412 DOT 282f0752 AT hem1 DOT passagen DOT se>
Comments: Authenticated sender is <billc AT blackmagic DOT tait DOT co DOT nz>
Precedence: bulk

On 30 Oct 97 at 17:37, Eli Zaretskii wrote:

> 
> On Thu, 30 Oct 1997, Peter Palotas wrote:
> 
> > >8MB is a borderline case.  The FAQ says to not use RAM drive for
> > >machines with 5-8MB, but for those with more than 8MB it suggests a
> > >2MB RAM disk.  With careful setup, a 8MB machine could well afford a
> > >small RAM drive and get a performance boost.
> > 
> > What should one put on the RAMDrive in this case? I mean what will give you
> > the largest performance boost? Putting GCC, CC1PLUS and those .exe files
> > there, or using it as the TMPDIR?
> 
> It depends on what exactly is loaded at boot time (TSRs, device
> drivers) and what kind of jobs do you do most.  In general, I don't
> recommend putting the compiler into the RAM disk, since the .exe are
> large and will quickly exhaust the RAM drive.  Let the disk cache
> handle these.  TMPDIR should be the first candidate for the RAM
> disk, then the headers (if you compile a lot).

The programs on my system has been compressed using djp, so it only 
takes up 50-60% of the normal space.  Using a 2.5M ramdrive with gcc, 
cc1, cc1plus, cpp and as leaves me with ~600 k from TMPDIR.  For me, 
this is almost always enough. The only time it fills up is when I 
compile one of my SWIG generated programs (600-700k .c file).


> But having only 8MB means that you need to experiment and time your
> real-life jobs to see which setup is best for you.  I don't think
> anybody can give you a reliable advice based on hearsay.  That's why
> the FAQ avoids saying anything specific for this borderline case
> (although I myself had an 8MB machine for several years).

Yes, it took very carefull fine tuning, and that was on a 12M 
machine.  For 8M, I think having a 1.5M RAM disk with the header 
files and temp directory but no disk cache or a disk cache only would 
be the way to go.  It all depends on what you're doing.  The problem 
with the disk cache (IMHO) is cc1 and cc1plus always fill it up 
killing the cached header files.  This is why I moved them onto a ram 
disk.

Bill
--
Leave others their otherness.