Comment Re:F5 IRule (Score 2, Informative) 928
I recommend using a data class rather than setting a global variable.
Data classes are compiled at configuration load and are static, whereas setting the global variable with each firing of the event absorbs a small amount of processing time to reset the variable. Setting global variables can also move TMM into a slower processing regime. As the HTTP_REQUEST event is very 'inner loop', it is best to optimize it as much as possible.
If you absolutely have to set a global variable with a semi-fixed value, I recommend doing it during the RULE_INIT event.
(As of July 1st, F5 is offering expanded iRule support to Premium and Premium Plus support contract holders. Call in with your troublesome iRules, and you have a somewhat decent chance of ending up with me at the other end of the phone.)
Data classes are compiled at configuration load and are static, whereas setting the global variable with each firing of the event absorbs a small amount of processing time to reset the variable. Setting global variables can also move TMM into a slower processing regime. As the HTTP_REQUEST event is very 'inner loop', it is best to optimize it as much as possible.
If you absolutely have to set a global variable with a semi-fixed value, I recommend doing it during the RULE_INIT event.
(As of July 1st, F5 is offering expanded iRule support to Premium and Premium Plus support contract holders. Call in with your troublesome iRules, and you have a somewhat decent chance of ending up with me at the other end of the phone.)