[gnu.emacs] GNU Emacs on Cray X/MP?

fouts@lemming.nas.nasa.gov.nas.nasa.gov (Marty Fouts) (08/30/88)

In article <20463@tut.cis.ohio-state.edu> bob@allosaur.cis.ohio-state.edu (Bob Sutterfield) writes:
>In article <523@nikhefh.hep.nl> i91@nikhefh.hep.nl (Fons Rademakers) writes:
>>Could somebody tell me if it possible at all to port GNU Emacs to a
>>Cray runnig Unicos 4.0? If so, did somebody already to this? If not,
>>why not?
>
>It's been done with an older version of Unicos.  But do you really
>want to do your work that way?
>
>The Cray vector architecture has fairly poor handling of character I/O
>and interrupts/context switches, at least in the conventional UNIX
>sense.  I suspect you'd get better performance (and bother the heavy
>crunchers on the Cray less) if you used ftp-find-file to keep the
>editing on your friendly local workstation or front-end host.  Do the
>compiling and debugging and big problem solving on the Cray, and keep
>the user interaction on a machine better suited to it.
>

WE use GNU on our Cray 2, and find that ftp-find-file would require
much more overhead on the 2 then using GNU does.  I've seen this
its-faster-not-to-do-characters-on-a-supercomputer reflex a lot of
times, but when I've measured it, it doesn't work out to be true.
ftp, especially of a long (>60K line) program for a small number of
changes is much more expensive than making the same changes in a
window.

It is true that interaction should happen on the front end and
computing on the back, but ftp-find-file isn't as effective as keeping
a shell window open, editing and doing recompiles locally.  Better yet
might be supdup with GNU split between the front and back end, ala
Pike's editor on the BLIT, but I haven't measured that, so I am only
speculating.


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