...
use Devel::Size qw[ total_size ];
...
unless( int( time ) % 3600 ) {
    open my $sizelog, '>', '/some/path/' . localtime() . '.log' or warn $!;

    print $sizelog "$_ =>", total_size( $::{ $_ } ) for sort keys %::;

    close $sizelog;
}

##</code><code>##

 :> 378
&#9788; :> 418
&#8597; :> 262
&#9644; :> 345
&#8616;ARNING_BITS :> 400
&#8593; :> 330
! :> 403
" :> 292
$ :> 272
+ :> 552
- :> 552
/ :> 382
0 :> 386
1 :> 425
2 :> 407
<none>:: :> 460
@ :> 950
ARGV :> 390
Devel::Size: Calculated sizes for compiled regexes are incompatible, and probably always will be
AutoLoader:: :> 25020
BEGIN :> 272
CORE:: :> 930
Carp:: :> 17283
Devel::Size: Calculated sizes for compiled regexes are incompatible, and probably always will be
Config:: :> 91676
DB:: :> 850
Devel::Size: Calculated sizes for compiled regexes are incompatible, and probably always will be
Devel:: :> 22891
Devel::Size: Calculated sizes for compiled regexes are incompatible, and probably always will be
DynaLoader:: :> 55547
ENV :> 6491
Devel::Size: Calculated sizes for compiled regexes are incompatible, and probably always will be
Exporter:: :> 23537
INC :> 1710
IO:: :> 928
Internals:: :> 3421
Mac:: :> 1725
PerlIO:: :> 2363
Regexp:: :> 933
SIG :> 3595
STDERR :> 274
STDIN :> 272
STDOUT :> 274
UNIVERSAL:: :> 1857
VMS:: :> 1248
Win32:: :> 11242
] :> 355
_ :> 345
_<..\perlio.c :> 336
_<..\universal.c :> 348
_<..\xsutils.c :> 340
_<.\win32.c :> 328
_<Size.c :> 339
_<c:/Perl/site/lib/auto/Devel/Size/Size.dll :> 479
_<dl_win32.c :> 330
_<perllib.c :> 328
attributes:: :> 947
Devel::Size: Calculated sizes for compiled regexes are incompatible, and probably always will be
main:: :> 299655
stderr :> 274
stdin :> 272
stdout :> 274
strict:: :> 6427
total_size :> 844
utf8:: :> 4344
Devel::Size: Calculated sizes for compiled regexes are incompatible, and probably always will be
vars:: :> 9566
warnings:: :> 58863