[ic] Iterations slow with mv_matchlimit incrementations

Grant emailgrant at gmail.com
Wed May 13 04:51:36 UTC 2009

>> >> 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
>> execute?
>> My installation is a year or two old.  Does this sound like a problem
>> an upgrade could fix?
> e-mail does not seem to be the most useful medium to do performance tests.
> Servers can start holding e-mails or other external influences can cause
> e-mails to arrive less frequently.
> Why not have 15 timestamps written to a logfile, so you can look at this
> data and see if you can find any trends. Is it that the 15 timestamps are
> increasing in interval equally?

Exactly, that seems to be the behavior.  They increase in interval equally.

- Grant

> So it was with
> ml=10:   time,  time+I,   time+I+I,  time+I+I+I    (10, 15, 20, 25 etc)
> ml=999999:   time,   time+(Ix10),  time+(Ix10+Ix10),  time+(Ix10+Ix10+Ix10)
> (10, 60, 110, 160 etc)
> or does ml=999999  show a less regular pattern where it has a spike between
> two timings?
> But you can imagine that it is shooting in a black hole here without
> actually seeing the code.
> CU,
> Gert

More information about the interchange-users mailing list