[ic] Iterations slow with mv_matchlimit incrementations

Grant emailgrant at gmail.com
Tue May 12 06:15:36 UTC 2009

>>> I have a somewhat complex chunk of IC code about 500 lines long.
>>> If I
>>> set the mv_matchlimit of the main loop to a small number, each
>>> iteration takes less than a second to execute.  However, as I
>>> increase
>>> the mv_matchlimit, each iteration takes longer to execute until it's
>>> quite slow.  I've been over my code again and again but I can't
>>> find a
>>> cause for this behavior.  The only clue I have is that each iteration
>>> executes much faster when the loop is almost done with all of its
>>> iterations.
>>> I'm wondering if the problem is "under the hood" of IC.  Does this
>>> scenario ring a bell for anyone?
>>> Thanks,
>>> Grant
>> I'm baffled by this.  I have no idea why increasing mv_matchlimit
>> would drastically increase the amount of time required for *each* loop
>> iteration.  Please let me know if you have any ideas.
> Is there any way you can post the relevant piece of code?  Without
> knowing what's being iterated over, it's hard to offer suggestions.
> In particular, are there any parts which are perl blocks of any
> particular flavor (calc, calcn, perl, prefix-exec, etc)?  Are there
> perhaps multiple nested loop constructs?
> Regards,
> David

Here's another illustration of my problem.  I set up 15 [email] tags
throughout my code so I get an email whenever certain points are
reached.  With ml=10 I get maybe 20 or so emails per second.  With
ml=999999 I get much less than 1 email per second.  My understanding
is that the first 10 iterations should take the same amount of time in
either scenario.

Does anyone know why IC would execute a single iteration at a
drastically slower rate, just because it has more total iterations to

My installation is a year or two old.  Does this sound like a problem
an upgrade could fix?

- Grant

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