From: bwv549 <jtprince@...>
Date: 2007-04-04T02:05:03+09:00
Subject: Re: implementing an array based class

> i'd love to see your tests using it.

Thanks for the insight.  I've included an arrayfields implementation
on the above benchmark:

Rehearsal --------------------------------------------------
ArrayFields      8.433333   0.800000   9.233333 (  5.585626)
Class1           5.566667   0.500000   6.066667 (  3.631757)
Class2           6.050000   0.550000   6.600000 (  3.963679)
Struct           3.583333   0.300000   3.883333 (  2.335911)
ArrayBased       2.033333   0.266667   2.300000 (  1.381698)
Array.new        1.950000   0.333333   2.283333 (  1.371351)
Array []         0.833333   0.316667   1.150000 (  0.689010)
---------------------------------------- total: 31.516667sec

                     user     system      total        real
ArrayFields      8.516667   0.816667   9.333333 (  5.609708)
Class1           5.366667   0.650000   6.016667 (  3.617349)
Class2           5.933333   0.566667   6.500000 (  3.893614)
Struct           3.616667   0.266667   3.883333 (  2.360849)
ArrayBased       1.933333   0.316667   2.250000 (  1.374079)
Array.new        1.883333   0.333333   2.216667 (  1.370410)
Array []         0.866667   0.283333   1.150000 (  0.696223)


Here's how I tested it (let me know if this is done incorrectly):

require 'arrayfields'
fields = %w(f1 f2 f3 f4 f5 f6 f7)

bmbm(15) do |re|
  re.report("ArrayFields") { REP.times { x = [*attribute_array];
x.fields = fields } }
  ## .... same as before
end

I haven't tested the memory on it, but it would appear to be
comparable to an Array (very low memory usage) from your
implementation.  It does have slightly higher overhead in the time
required for creation (if I did it correctly).  Nonetheless,
arrayfields seems ideal for database work as you can simply label the
fields without creating new classes for everything.  In the particular
case before me, I have only a handful of object types, but lots of
them.

Thanks,
john