[Emacs-ada-mode] OT: hardware required to run Debian

[Ludovic Brenta]

Stephen Leake writes:
>> As far as I'm concerned, I'm undecided whether I should include
>> gnatpath in a next release of gnat-4.1 (which I maintain) or as part
>> of ada-mode (which I don't, but since the maintainer seems MIA, I
>> could take the package over).
>
> It is dependent on the compiler version, since it uses internal
> compiler files. So it makes the most sense to distribute it with the
> compiler.

Not necessarily. In Debian, two libraries (libgnatvsn under GMGPL and
libgnatprj under GPL) expose the compiler's internals to all who need
them.  GPS for example uses these libraries, as do most ASIS-based
tools.  So it's really not a problem to package something that needs
those internals separately from the compiler.

> I suppose it's time for me to set up a Debian box and consider
> becoming the Ada mode maintainer for that as well. I should be
> testing Ada mode on something other than Windows anyway.

:)

> What would you recommend as a reasonable Debian box? I can use my
> current Windows laptop as an X display, so I only need the CPU and
> disks.

My installation uses 2.7 Gb on disk (my data takes 15G).  Granted, it
has no GNOME, no KDE, no Evolution, no Firefox... just emacs, X and
galeon.  But it does have OpenOffice.org, a couple of games and lots
of development tools and libraries, including GPS, gnat-gdb, monotone,
etc.  If you want everything, perhaps before you decide between the
various desktops, you'll need 4-6G.

CPU-wise, Linux generally requires less muscle than Windows does.  I
even know people who run GNU/Linux on ancient i486 boxes.  A
Pentium-II is enough for Emacs, ada-mode, and compiling such a small
program as gnatpath.

Memory-wise, if you don't run an X server (the X server would be on
your laptop), you'll be fine with 128M.  That's enough to run emacs
and compile small programs with GNAT.
 
As for me, I used a ThinkPad T22 for years.  It was adequate, with a
Pentium-III @900 MHz, 20G disk, and 256M RAM.  I could run X, emacs,
OpenOffice and most large programs at the same time without too much
trouble.  But after I switched the compiler from gnat 3.15p to GCC
4.1, the memory and CPU requirements for builds went way up.  Also,
working on the GCC 4.1 sources (2.6 million SLOC) as opposed to the
gnat 3.15p ones (750 kSLOC) pushed my ThinkPad to its limits.  For
example, compiling GPS 4.0.1 would take 220 minutes, and building
gnat-4.1 almost 7 hours.  The disk was too small to contain a full
replica of the Subversion repository (9.5 Gb).  That, BTW, is what got
me looking for alternatives and I settled on Monotone.  Still, I made
by for a year before I switched, and I even did all of the transition
to GCC 4.1 and all packages on that machine.

Now I've just switched to a dual-core amd64 laptop, 2GHz, 2 G RAM, and
80 G disk.  The 2 G of RAM is overkill; I could have lived with as
little as 768M with no swapping, even while compiling GPS with
gnatmake -j2.  But what the heck; now I have a large disk cache :) and
GPS compiles in just 22 minutes.  I haven't recompiled gnat-4.1 yet
but I think it would take approximately one hour and a half, because
the Makefiles only use one CPU.  Maybe I'll tweak the build scripts to
take advantage of the two cores... :)

-- 
Ludovic Brenta.