If I run this:
perl -MTime::HiRes=time -wE"my $t=time; my @a=1..1e6;say time-$t; <>"
0.0623979568481445
It takes 6/100ths sec; consumes 84MB and causes 24,000 page faults.
This:
perl -MTime::HiRes=time -wE"my $t=time; my @a=map $_,1..1e6;say time-$
+t; <>"
0.216002941131592
2/10ths ec; 108MB; 30,000 page faults.
But this:
perl -MTime::HiRes=time -wE"my $t=time; my @a=map $_,map $_,1..1e6;say
+ time-$t; <>"
31.4807999134064
32 seconds; 140MB; 5.7 million page faults?
But most confusingly:
perl -MTime::HiRes=time -wE"my $t=time; my @a=map $_,map $_,1..5e5;say
+ time-$t; <>"
7.87800002098084
8 seconds; 72MB; 1.5 million page faults.
Any thoughts where to start looking?
This is Perl 5.10.1 (AS1007) 64-bit on windows. Other platforms are almost certainly not affected.
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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