Ok. Here you go:
#! perl -slw
use strict;
use Benchmark qw[ cmpthese ];
our $packedV = pack 'V*', 1 .. 1e6;
our $packedW = pack 'w*', 1 .. 1e6;
our $packedVec = ''; vec( $packedVec, $_, 32 ) = $_ for 0 .. 1e6 - 1;
cmpthese -5, {
unpackV => q[ my @nums = unpack 'V*', $packedV; ],
unpackW => q[ my @nums = unpack 'w*', $packedW; ],
unVec => q[
my @nums; push @nums, vec( $packedVec, $_, 32 ) for 0 .. 1e6 -
+ 1
],
};
print "$_: ", length( do{ no strict; ${$_} } )
for qw[ packedV packedW packedVec ];
__END__
C:\test>junk0
Rate unVec unpackV unpackW
unVec 1.87/s -- -29% -31%
unpackV 2.64/s 41% -- -2%
unpackW 2.70/s 44% 2% --
packedV: 4000000
packedW: 2983490
packedVec: 4000000
unpack 'w' is 44 % faster than vec and compresses the data to 75% to boot. Which means less time to transfer from the DB.
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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