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Re: Unexpected delay in using arguments.

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  Re: Unexpected delay in using arguments. Bize Ma <binaryzebra@gmail.com> - 2018-08-14 23:17 -0400

#14491 — Re: Unexpected delay in using arguments.

> Of course I assume this is only a proxy simpler reproducer
> for the actual problem program

Of course this is a "reproducer" of the issue.

> but just the same it is almost always possible
> to refactor a program into a different algorithm that avoids the need
> to enumerate so many arguments in memory.

As you say: "almost".

Take a look at the Stéphane Chazelas example to convince yourself.



2018-08-14 17:50 GMT-04:00 Bob Proulx <bob@proulx.com>:

> I followed along through the script:
>
> >     m=20000
> ...
> >     test1() { ...
>
> Eventually I got to this line:
>
> >       set -- $(seq $m)
>
> At that line I see that bash must allocate enough memory to hold all
> of the numbers from 1 through 20000 in memory all at one time.  That
> is very inefficient.  That is at least 100K of memory.
>
>   $ seq 20000 | wc -c
>   108894
>
> Of course I assume this is only a proxy simpler reproducer for the
> actual problem program but just the same it is almost always possible
> to refactor a program into a different algorithm that avoids the need
> to enumerate so many arguments in memory.  I suggest refactoring the
> program to avoid the need for this memory stress.
>
> Bob
>

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