For comparison, here are the pre-optimization figures for perl-5.6.1, XML::SAX::PurePerl-0.08 from CPAN:

$ perl -d:DProf t/16large.t
1..3
ok 1
ok 2
parsed 80085 bytes in 13 seconds
ok 3
$ dprofpp -O 6
Total Elapsed Time = 11.05672 Seconds
  User+System Time = 10.67672 Seconds
Exclusive Times
%Time ExclSec CumulS #Calls sec/call Csec/c  Name
 36.9   3.940  3.892 115004   0.0000 0.0000  XML::SAX::PurePerl::Reade
+r::match_nonext
 14.8   1.590  1.547  86892   0.0000 0.0000  XML::SAX::PurePerl::Reade
+r::Stream::next
 10.8   1.160  8.197 114995   0.0000 0.0001  XML::SAX::PurePerl::Reade
+r::match
 9.55   1.020  7.152 115004   0.0000 0.0001  XML::SAX::PurePerl::Reade
+r::match_nocheck
 9.27   0.990  2.450  86891   0.0000 0.0000  XML::SAX::PurePerl::Reade
+r::nextchar
 9.05   0.966  8.389  17607   0.0001 0.0005  XML::SAX::PurePerl::Reade
+r::consume
[download]

Same machine, same perl, cvs version of fifteen minutes ago:

$ perl -d:DProf t/16large.t
1..3
ok 1
ok 2
parsed 80085 bytes in 16 seconds
ok 3
$ dprofpp -O 6
Total Elapsed Time = 13.08672 Seconds
  User+System Time = 11.91672 Seconds
Exclusive Times
%Time ExclSec CumulS #Calls sec/call Csec/c  Name
 37.5   4.480  4.442 115004   0.0000 0.0000  XML::SAX::PurePerl::Reade
+r::match_nonext
 13.2   1.580  1.537  86892   0.0000 0.0000  XML::SAX::PurePerl::Reade
+r::Stream::next
 10.6   1.270  9.037 114995   0.0000 0.0001  XML::SAX::PurePerl::Reade
+r::match
 10.2   1.220  7.882 115004   0.0000 0.0001  XML::SAX::PurePerl::Reade
+r::match_nocheck
 9.02   1.075  9.239  17607   0.0001 0.0005  XML::SAX::PurePerl::Reade
+r::consume
 8.48   1.010  2.460  86891   0.0000 0.0000  XML::SAX::PurePerl::Reade
+r::nextchar
[download]

It looks like a pessimization for for this machine. Both build directories were on the same spindle and partition.

After Compline,
Zaxo