Re: GCL slow reading files

On 4/10/26 8:27 AM, Raymond Toy wrote:

> On 4/10/26 12:27 AM, David Scherfgen wrote:
>
>> Raymond Toy <[email protected]> schrieb am Fr., 10. Apr. 2026, 00:27:
>>
>>     On 4/9/26 8:33 AM, Leo Butler wrote:
>>
>>>     To see what I mean, start a fresh maxima+gcl build and do:
>>>
>>>     showtime:true $
>>>     load(draw);
>>
>>     On my fairly fast machine, ecl takes about 3.3 sec. gcl takes 65
>>     sec; ccl64, 0.57 sec; cmucl, 2.2 sec. Ccl is known for having a
>>     very, very fast compiler.
>>
>> On my machine, GCL takes 2.4 seconds to load "draw". But it uses an 
>> older version of GCL, namely 2.6.14. Maybe the "slowness" was 
>> introduced with 2.7.x.
>>
>> I could confirm that GCL 2.6.14 too is quite slow in reading files. 
>> Reading a 50 MB file took more than 4 seconds on a lightning fast 
>> NVMe SSD with ZFS and a huge cache on top.
>
> Wow, it’s much worse with 2.7.2:
>
A bit of googling pointed me to |si:fread|. For a file of (unsigned-byte 
8), it is much, much faster:

|(with-open-file (s "doc/info/maxima.info-1" :direction :input 
:element-type '(unsigned-byte 8)) (let* ((len (file-length s)) (buf 
(make-array len :element-type '(unsigned-byte 8)))) (time (prog1 t 
(si:fread buf 0 len s))))) real time : 0.010 secs run-gbc time : 0.000 
secs child run time : 0.000 secs gbc time : 0.000 secs allocation : 0 
Mbytes |

Didn’t check to see if buffer has the right values though.

&#8203;

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