iRule with table apparently leaking memory

I did find SOL12245, which details a known memory leak in the table keys -subtable command, which we use. However, it specifically states that it doesn't apply to the command when the -count option is used, which is the only way that we use it. I can't see any other reason for the memory leak, unless the expiration only applies to keys, but the subtables never expire?

TIA for any help:

when RULE_INIT {

set ::pdfappmaxRate 20 ;set later per user from class

set static::pdfappwindowSecs 300 ;global

}

when HTTP_REQUEST {

if { [HTTP::method] eq "GET" } {

Check to make sure the user is not in a redirect loop because of not accepting cookies

if { (([HTTP::uri] contains "?tag=1?tag=1") or ([HTTP::uri] contains "&tag=1&tag=1")) } {

HTTP::redirect "http://ieeepdfapp.site.com/pdfapp/cookiedetectresponse.jsp"

}

if { (([HTTP::uri] contains "stamp.jsp") or ([HTTP::uri] contains ".pdf")) and not ([HTTP::header exists Range ]) and ([HTTP::cookie exists ERIGHTS])} {

log local0. "pdfapp PDF Initial download detected."

Extract clients IP address

set client_ip [IP::remote_addr]

set pdfapp_session [HTTP::cookie ERIGHTS]

set mypdfappMaxRate $::pdfappmaxRate

set pdfnum [table incr "pdfapp:$pdfapp_session"]

set orig_ip [table lookup -subtable session_map $pdfapp_session]

log local0. "Session ID $pdfapp_session should have IP [table lookup -subtable session_map $pdfapp_session]"

log local0. "Client actually has IP $client_ip"

table lifetime pdfapp:$pdfapp_session 3600

table timeout pdfapp:$pdfapp_session 3600

log local0. "Client $client_ip has $pdfnum total hits"

set tbl "countpdf:$pdfapp_session"

table set -subtable $tbl $pdfnum "ignored" indef $static::pdfappwindowSecs

log local0. "Client $pdfapp_session has: [table keys -subtable $tbl -count] pdf downloads in the past $static::pdfappwindowSecs seconds"

if { [table keys -subtable $tbl -count] > $mypdfappMaxRate } {

log local0. "PDF Abuse - User $client_ip, Session $pdfapp_session"

HTTP::respond 200 content {"Slow Down!"

}

return

}

}

}

}