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Forum Discussion

Carol_Williams_'s avatar
Carol_Williams_
Icon for Nimbostratus rankNimbostratus
Oct 28, 2009

help optimize iRule

Could someone please help me. I have a redirect iRule that is slow. I need to make sure all images are 1 not going through my httpclass profile and 2 if they are coming from a list of BOTs going to ...
application delivery
dev
devops
iRules
hoolio's avatar
hoolio
Icon for Cirrostratus rankCirrostratus
Oct 28, 2009
Hi Carol,

For your iRule... 

 
 when HTTP_REQUEST { 
    if { [matchclass [HTTP::uri] ends_with ::images] } { 
       if { [matchclass [HTTP::header User-Agent] contains ::robots] } { 
          pool MyBotPool 
       } else { 
          pool MyImagePool 
    } 
    HTTP::class disable 
    } 
 }

...the HTTP class selection is being disabled on every request. Is this what you intended?

Can you clarify what you are trying to use an HTTP class for? Also, which LTM version are you running?

When you say the iRule is slow under load, can you provide more detail? How are you quantifying the slowness? Is the slowness occurring for all requests from all User-Agents--or just specific clients or specific requests?

Are you seeing high TMM CPU utilization in tmstat output or the performance graphs? Do you think it's an LTM resource issue?

Aaron