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Re: Unexpected delay in using arguments.

Started byBob Proulx <bob@proulx.com>
First post2018-08-14 15:50 -0600
Last post2018-08-14 15:50 -0600
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  Re: Unexpected delay in using arguments. Bob Proulx <bob@proulx.com> - 2018-08-14 15:50 -0600

#14487 — Re: Unexpected delay in using arguments.

FromBob Proulx <bob@proulx.com>
Date2018-08-14 15:50 -0600
SubjectRe: Unexpected delay in using arguments.
Message-ID<mailman.5110.1534283444.1292.bug-bash@gnu.org>
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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