Perl uses reference counting, not garbage collection. Everything is freed as soon as there is no reference to it.

Any memory freed by Perl might not be returned to the OS, but it will become available to Perl for reuse.

Update: For example, 

print("Check size of process $$ and press ENTER.");  # 1676K
<STDIN>;

$a .= ' '
   for 1..100_000;

print("Check size of process $$ and press ENTER.");  # 1920K
<STDIN>;

undef $a;
$a .= '!'
   for 1..100_000;

print("Check size of process $$ and press ENTER.");  # 1920K
<STDIN>;

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In reply to Re: Is there a way to invoke perl's garbage collector? by ikegami
in thread Is there a way to invoke perl's garbage collector? by Anonymous Monk

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