I have put systematically my in the foreach (or in the smallest possible scope), and guess what 'for my' is actually consistently slower in case B. Somehow it surprised me :( 

% stephan@labaule (/home/stephan) %
% for _i in {1..5}
> do
>   echo ===$_i====
>   perl -W perf_test_allmy.px            
>   echo --- 
>   perl -W perf_test.px
> done
===1====
Section A took 1.7020 CPU seconds
Section B took 3.9560 CPU seconds
Section A took 1.7330 CPU seconds
Section B took 3.9660 CPU seconds
---
Section A took 1.7020 CPU seconds
Section B took 3.6850 CPU seconds
Section A took 1.7420 CPU seconds
Section B took 3.7760 CPU seconds
===2====
Section A took 1.7220 CPU seconds
Section B took 4.0160 CPU seconds
Section A took 1.7030 CPU seconds
Section B took 4.0860 CPU seconds
---
Section A took 1.7220 CPU seconds
Section B took 3.7850 CPU seconds
Section A took 1.7230 CPU seconds
Section B took 3.6750 CPU seconds
===3====
Section A took 1.7120 CPU seconds
Section B took 4.0960 CPU seconds
Section A took 1.7220 CPU seconds
Section B took 4.0460 CPU seconds
---
Section A took 1.7320 CPU seconds
Section B took 3.5250 CPU seconds
Section A took 1.7220 CPU seconds
Section B took 3.6450 CPU seconds
===4====
Section A took 1.7020 CPU seconds
Section B took 4.1260 CPU seconds
Section A took 1.7120 CPU seconds
Section B took 3.9360 CPU seconds
---
Section A took 1.7020 CPU seconds
Section B took 3.8560 CPU seconds
Section A took 1.7430 CPU seconds
Section B took 3.6350 CPU seconds
===5====
Section A took 1.7020 CPU seconds
Section B took 4.1560 CPU seconds
Section A took 1.7120 CPU seconds
Section B took 3.9760 CPU seconds
---
Section A took 1.7220 CPU seconds
Section B took 3.7350 CPU seconds
Section A took 1.7330 CPU seconds
Section B took 3.5850 CPU seconds

[download]
hth --stephan

In reply to Re: Garbage collection problem?? by sgt
in thread Garbage collection problem?? by tcarmeli

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