Dnia Mon, 01 Feb 2010 17:36:11 +0300, Stas Boukarev napisał(a):
> On Mon, Feb 1, 2010 at 12:08 PM, Tamas K Papp <tkpapp@...> wrote:
>> Hi,
>>
>> Currently, I am using SBCL on 32-bit Ubuntu (x86). I ran into a
>> specific limitation (fixnum limits my array size), so am wondering
>> whether to switch to 64-bit SBCL. This would require a reinstall,
>> which is not a major issue but a minor PITA which would surely take a
>> few hours. Before I undertake this, I have a few questions:
>>
>> - how big is ARRAY-TOTAL-SIZE-LIMIT on 64-bit SBCL? Will this allow
>> me to use larger arrays? Is there another limit (provided that I
>> take enough memory with a --dynamic-space-size)?
> ARRAY-TOTAL-SIZE-LIMIT is (- most-positive-fixnum 2) and will indeed
> allow using larger arrays.
>
>> - Does 64-bit result in significantly a higher memory consumption? I
>> understand that fixnums will now take twice the space, but does
>> anything else take up more memory?
> Pointers will take double memory as well. I don't have a 64-bit machine
> at hand, and I don't remember how much more memory it consumes, but the
> core image is almost twice as large.
>
>> - Does 64 vs 32 bit have any impact on speed (positively or
>> negatively)? Can single floats be unboxed in 64-bit?
>>
> Yes, single floats are immediate. And 64-bit sbcl uses SSE2 for float
> and complex operations.
Hi,
I have SBCL on 64-bit Ubuntu
In my computer :
ARRAY-TOTAL-SIZE-LIMIT
1152921504606846973
I have installed sbcl using :
sudo apt-get install slime cl-swank sbcl
echo '(setq inferior-lisp-program "sbcl")' >> ~/.emacs
I'm intresting in using bigger memmory in SBCL.
Should I compile SBCL from sources ?
Regards
Adam
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