I encountered a strange regexp which was causing my mod_perl program to thrash, and have created a minimal case which causes it to do so: 
my $x = 1;
while(1) {
  my $text = "a" x $x;
  $text =~ s/(\w+){$x}//;
  print "x = $x ; OK\n";
  $x++;
}

[download]
As you can see, it starts to get really slow around 20 and gets exponentially worse from there. Hast thou any idea wtf is going on?

In reply to regexp hang? by cxreg

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