tcl memory keep growing and LTM no response

Question

Hi,&nbsp;
&nbsp;One of our customer uses the following iRules to perform persistent and finds the tcl memory in statistics keep growing and caused the LTM no response.&nbsp;
&nbsp;Has anyone seen the symptoms?  I think the iRule is quite common.  Thanks in advance!&nbsp;
&nbsp;rule us_web_iRule {
&nbsp;   when CLIENT_ACCEPTED {
&nbsp;  set add_persist 1
&nbsp;}
&nbsp;when HTTP_RESPONSE {
&nbsp;  if { [HTTP::cookie exists "JSESSIONID"] and $add_persist } {
&nbsp;    persist add uie [HTTP::cookie "JSESSIONID"]
&nbsp;    set add_persist 0
&nbsp;  }
&nbsp;}
&nbsp;when HTTP_REQUEST {
&nbsp;  if { [HTTP::cookie exists "JSESSIONID"] } {
&nbsp;    persist uie [HTTP::cookie "JSESSIONID"]
&nbsp;  } else {
&nbsp;    set jsess [findstr [HTTP::uri] "jsessionid" 11 ";"]
&nbsp;    if { $jsess != "" } {
&nbsp;      persist uie $jsess
&nbsp;    }
&nbsp;  }
&nbsp;}
&nbsp;}&nbsp;&nbsp;
&nbsp;Regards,
&nbsp;Ken (k.wong@f5.com)&nbsp;

colin_walker_12 · Answer

I don't see anything in that rule that would cause the memory consumption to continue increasing. &nbsp;
&nbsp;I'd probably fix the logic around the first if statement to be sure you're checking to see what the value of $add_persist is, not just that it exists...but I wouldn't think that would cause the behavior you're describing.&nbsp;
&nbsp;Have you tried adding some logging statements to ensure that things are firing the way you expect them to?&nbsp;
&nbsp;Colin

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