From: ahoward <ahoward@...>
Date: 2003-04-24T01:00:23+09:00
Subject: Re: Performance test: 1.8.0p2 versus 1.6.8

On Wed, 23 Apr 2003, [iso-8859-1] Jos� Santos Alegria wrote:

> Thanks! I did try it and got just a 10% improvement. The 1.6.8 version is still faster.
>
> 1. Ruby 1.6.8 under Linux   (fields=line.split(";", -1); n_fields+=fields.length) ==> 57 seconds
> 2. Ruby 1.8.0p2 under Linux (fields=line.split(";", -1); n_fields+=fields.length) ==> 83 seconds
> 3. Ruby 1.6.8 under Linux   (fields=line.split(/;/, -1); n_fields+=fields.length) ==> 59 seconds
> 4. Ruby 1.8.0p2 under Linux (fields=line.split(/;/, -1); n_fields+=fields.length) ==> 65 seconds
> 5. Python 2.2.2 under Linux (fields=line.split(";");     n_fields+=len(fields))   ==> 54 seconds
>
> So, your suggestion did improve performance but nevertheless 1.8.0p2 is
> still slower than 1.6.8 and I believe it shouldn't! Could it be the result
> of increased garbage collection on the 1.8.0p2 version? The file I'm
> processing is reasonably large: 400MB with 3.5 million lines! BTW how can I
> obtain the time spent by Ruby on garbage collection and the number of times
> it was executed?

i'm not sure how smart it would be with a file that large, but you could
compare the times of your program with one begining with

  GC.disable

in order to guestimate the percentage of time actually taken by the GC.

i really don't know how accurate that would be, but if the difference was
significant you should be able to see some difference - either that or
GC.disable - doesn't.

-a

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