Re^10: Performance oddity when splitting a huge file into an AoA

[Xenofur]

As the nytprof files are binary, I can't upload them here. Instead I've made an effort to make the next batch of benchmarks more useful: http://drop.io/perl_performance/asset/arrays-zip

I've taken your suggestions and implemented them. Also, there's only two variants this time, as one of them shows the performance issue and the other one has a tiny change which resolves the issue to an extent.

Sidenote: Are you available on IRC? This stuff is very time-consuming and I'm way out of my depth here, so the only thing i literally can do is provide info in the hopes it helps others, but with the delays involved in the form of communication here i'm getting incredibly frustrated.

[BrowserUk]

Having spent a couple of hours flicking between the two sets of results in your latest zip, I am at a loss to explain or reproduce the problem. I doesn't make any sense at all to me why

my @line_arr = split ',', $line;

would take 8 times longer in one run relative to another. Assuming the same interpreter is being used for both runs.

As I cannot reproduce it, and nobody else has spoken up to say that they can, it would appear to be confined to your system. If you have a work around, and are not concerned that this will adversely affect your other programs, then simply drop the issue.

Quite frankly, I find this NYT prof output very difficult to use. Pretty, but otherwise essentially useless. But, once again, I seem to be in a minority here.

[Xenofur]

You mean running this in 32 bit ActivePerl or Strawberry Perl doesn't do this on your system? And yes, the two results in the latest zip are from the same interpreter.

As for NYTProf, I'm only using it because nothing different was suggested and because it is the most advanced of the profilers i know.

Either way, thanks a lot for your time and assistance with this. :)

[roubi]

You've had the change that seems to (inexplicably) resolve the performance issue for a week now. Does your frustration comes from not being able to use it for some reason? Or are you like me impatient to find out what the heck this one is about? :)

[Xenofur]

Exactly this. :)

I could've walked away long ago, but i really want to fix this in one way or another for good. It's just a bit hard to justify 1-2 hours of expense whenever i sit down to think up ways to modify the code, muck around with different Perl installations, run the benchmarks, try to get it all in a presentable format and write up short descriptions of what i did. (Plus, i get to spend hours after what worrying and wondering if i missed something.)