write_data spends too much time to create file.


On Thu, 29 Jul 2010, Alejandro Morales wrote:

< Dear Leo:
< My output is:
< 
< showtime:true $
< array(new,1000,1) $
< for a:0 thru 1000 step 1 do (new[a,0]:a,new[a,1]:a+1) $
< write_data(new,"new.dat");
< Evaluation took 0.0000 seconds (0.0000 elapsed) using 40 bytes.
< Evaluation took 0.0000 seconds (0.0000 elapsed) using 16.008 KB.
< Evaluation took 0.0880 seconds (0.0896 elapsed) using 1.131 MB.
< Evaluation took 0.0960 seconds (38.1753 elapsed) using 1.988 MB.

You can see that Maxima reports it took 0.096 sec to evaluate the last
command, but that 38.175 sec elapsed. I think this indicates that the
slowdown is occuring while writing. 

Perhaps someone with a 64bit system could check this.

Could you try another lisp, say Maxima built with cmucl lisp, to
see if this problem is particular to clisp?

Leo

< 
< build_info();
< 
< Maxima version: 5.21.1
< Maxima build date: 20:45 6/2/2010
< Host type: x86_64-unknown-linux-gnu
< Lisp implementation type: CLISP
< Lisp implementation version: 2.44.1 (2008-02-23) (built 3465369225) (memory
< 3484518319)
< 
< Evaluation took 0.0000 seconds (0.0006 elapsed) using 38.320 KB.
< Where the problem is?
< Thanks: Morales
< 
 


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