Juho Snellman  <jsnell@iki.fi> wrote:
+---------------
| Other than that, the main reasons for using a 64-bit SBCL right now are:
|   * You have an Athlon 64, your Linux distribution is pure 64-bit without
|     a 32-bit compatibility environment, and you don't want to run a 32-bit
|     chroot.
+---------------

Say what? Which x86_64 Linux *doesn't* have a 32-bit compatibility
environment installed by default?!?

Anyway, FWIW, my workstation at work is an Athlon64 3600+ (?)
with a 1.8 GHz clock (I think, can't see the label at the moment
but "dmesg" says "3591.37 BogoMIPS" and "Detected 1802.357 MHz
TSC timer") running Linux 2.4.21-20.EL (some RedHat distro),
and it runs the pre-compiled 32-bit CMUCL-19a binary just fine:

    > (time (dotimes (i 2000000000)))
    ; Compiling LAMBDA NIL: 
    ; Compiling Top-Level Form: 

    ; Evaluation took:
    ;   2.22f0 seconds of real time
    ;   2.22f0 seconds of user run time
    ;   0.0f0 seconds of system run time
    ;   4,011,445,780 CPU cycles
    ;   0 page faults and
    ;   0 bytes consed.
    ; 
    NIL
    > 

Compare this with the same CMUCL-19a on a 32-bit Athlon laptop
running FreeBSD [which says "mobile AMD Athlon(tm) XP2500+
(1855.20-MHz 686-class CPU)" and "Timecounter TSC frequency
1855201003 Hz"]:

    > (time (dotimes (i 2000000000)))
    ; Compiling LAMBDA NIL: 
    ; Compiling Top-Level Form: 

    ; Evaluation took:
    ;   2.18f0 seconds of real time
    ;   2.160405f0 seconds of user run time
    ;   0.0f0 seconds of system run time
    ;   4,039,789,390 CPU cycles
    ;   0 page faults and
    ;   0 bytes consed.
    ; 
    NIL
    > 

Virtually identical, yes?

So, yes, while a 64-bit CMUCL would be interesting, I'm
really glad that the 32-bit CMUCL "just runs" on Athlon64!


-Rob

-----
Rob Warnock			<rpw3@rpw3.org>
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