If you are matching many instances of this (say reading a log file that is 700MB or more and checking each line for this string) then you are likely to find that the performance improves if you:

• tie the match down to the bare minimum of wildcard characters,
• specify everything that you know is going to be in the match,
• and also anchor the match where possible to the beginning and end of the string (or line) so it doesn't have to try iterating over the string...

use strict;
use warnings;

my $line = "SNMPv2-MI::enterprises.343.2.10.3.5.100.1.0=INT";

my $match = $1 if $line =~ /^SNMPv2-MI::enterprises([0-9\.]+)=INT$/;
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