When I execute the following code with certain data, it takes a long, long time (~10 seconds on a fairly fast machine) to return. 

if ($text =~ /($searchString)/) {

   $_ = $1;
   s/!CR!/\n/g;
   print "$_\n";
} else {
   print "No match\n";
}

[download]

These are the values of $searchString and $text going into the regular expression. I apologize for the length, but this is as much as I've been able to narrow down the problem. 

$searchString : (?:.(?!!CR!))*.?-------(?:.(?!!CR!))*.?!CR!(?:.(?!!CR!
+))*.?!CR!(?:.(?!!CR!))*.?!CR!(?:.(?!!CR!))*.?node(?:.(?!!CR!))*.?!CR!
+(?:.(?!!CR!))*.?id(?:.(?!!CR!))*.?NEW ALERT(?:.(?!!CR!))*.?!CR!(?:.(?
+!!CR!))*.?borg(?:.(?!!CR!))*.?!CR!(?:.(?!!CR!))*.?subsys(?:.(?!!CR!))
+*.?!CR!(?:.(?!!CR!))*.?severity(?:.(?!!CR!))*.?!CR!(?:.(?!!CR!))*.?!C
+R!(?:.(?!!CR!))*.?nohup(?:.(?!!CR!))*.?!CR!(?:.(?!!CR!))*.?Id(?:.(?!!
+CR!))*.?!CR!(?:.(?!!CR!))*.?Team(?:.(?!!CR!))*.?!CR!(?:.(?!!CR!))*.?!
+CR!(?:.(?!!CR!))*.?!CR!(?:.(?!!CR!))*.?REPORT(?:.(?!!CR!))*.?Resource
+(?:.(?!!CR!))*.?slow -(?:.(?!!CR!))*.?

$text : ------------------------------------------------------------!C
+R!!CR!11/19/2001 16:20:23!CR!node_name[sanitized]!CR!id[987987] NEW A
+LERT!CR!borg[this.also.sanitized]!CR!subsystem[this.too] ERR-5555!CR!
+severity[warning] group[sanitized-host]!CR!!CR!nohup /usr/local/bin/n
+otreal!CR!Id: 987987!CR!Team[TEST_Services]!CR!!CR!ACTION: Send Voice
+ Mail to [555-3423 555-9922]!CR!REPORT: Process syslog has crashed " 
+garbage garbage!CR!--------------------------------------------------
+----------!CR!!CR!

[download]

I have been looking at the output generated by use re 'debug'; but without much success. I can see that it seems to loop over the same string over and over, but I'm not sure why.

I would enormously appreciate any insight.

Examine

In reply to Regex runs for too long by examine

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