take this example. I get 56 with 5.8 32-bit but 176 with 64-bit perl5.10. 
perl -MDevel::Size=total_size -MDevel::Peek -e 'my @a; my $s = total_s
+ize(\@a);print "\nSIZE : $s\n";  Dump \@a, 1'

SIZE : 56
SV = RV(0x822f26c) at 0x8184a60
  REFCNT = 1
  FLAGS = (TEMP,ROK)
  RV = 0x8184b14
  SV = PVAV(0x8186c54) at 0x8184b14
    REFCNT = 2
    FLAGS = (PADBUSY,PADMY)
    IV = 0
    NV = 0
    ARRAY = 0x0
    FILL = -1
    MAX = -1
    ARYLEN = 0x0
    FLAGS = (REAL)

[download]
with 5.10 

sankaran@invest5.hyd:/u/sankaran/base/src/perl/Deshaw/PDL>  /usr/local
+/bin/perl5.10  -MDevel::Size=total_size -MDevel::Peek -e 'my @a; my $
+s = total_size(\@a);print "\nSIZE : $s\n";  Dump \@a, 1'

SIZE : 176
SV = RV(0x417520) at 0x417510
  REFCNT = 1
  FLAGS = (TEMP,ROK)
  RV = 0x4b1ba8
  SV = PVAV(0x41a388) at 0x4b1ba8
    REFCNT = 2
    FLAGS = (PADMY,RMG)
    MAGIC = 0x57dd10
      MG_VIRTUAL = &PL_vtbl_arylen_p
      MG_TYPE = PERL_MAGIC_arylen_p(@)
      MG_FLAGS = 0x02
        REFCOUNTED
    ARRAY = 0x0
    FILL = -1
    MAX = -1
    ARYLEN = 0x0
    FLAGS = (REAL)

[download]

In reply to Re^3: perl5.10 Devel::Size behaviour changed? by sang1986
in thread perl5.10 Devel::Size behaviour changed? by sang1986

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