From: "Aleksi Niemelä" <aleksi.niemela@...>
Date: 2000-12-16T07:48:36+09:00
Subject: [ruby-talk:7360] Re: Ruby performance question

Eric Crampton reports:
> > > Running on a small dataset of 13 MB of data (around 81000 
> > > lines), the
> Incidently, I tried disabling GC and running it on my small dataset
> (13 MB) which I would think would fit in physical memory. Somehow, the
> way Ruby is organizing data in memory causes it to store far, far, far
> more than 13 MB. I ran out of physical memory (1 GB of RAM) and it
> went into swap. :-(

No wonder, although I can't show any math to back me up (I'm shamed of my
poor skills :).

> while line = $stdin.gets.chomp!
>  line.split(",").each { |f|
>     fid, val = f.split("=")
>     h[fid] = val
>   }

But there will be (at least) 81 000 times an array creation of 81 000 *
avg_pair_count_on_line created strings. Then each of those strings create
yet again an array which is filled with two created strings. We shouldn't
discard strings created by gets either.

I don't know if there's something more.

	- Aleksi