Hello Albert, 4.4.7 is over three years old. Before you invest more time in this issue, I would suggest that you update to a maintained version (e.g. 5.4.x or 5.5.x). There have been many extensions to the code base and also bug fixes to since this time. The numbers from the memory debugging below basically list the allocated memory from these functions. They should normally not grow endless. There are also ways to output information to the log file, described e.g. here: http://www.kamailio.org/wiki/tutorials/troubleshooting/memory Cheers, Henning -- Henning Westerholt – https://skalatan.de/blog/ Kamailio services – https://gilawa.com<https://gilawa.com/> From: Albert Petit &lt;albertpetit(a)gmail.com&gt; Sent: Monday, September 13, 2021 10:34 PM To: Henning Westerholt &lt;hw(a)skalatan.de&gt; Cc: Kamailio (SER) - Users Mailing List &lt;sr-users(a)lists.kamailio.org&gt;rg>; SIP Router - Kamailio (OpenSER) and SIP Express Router (SER) - Users Mailing List &lt;sr-users(a)lists.sip-router.org&gt; Subject: Re: [SR-Users] Question about suspected memory leak presence module hi using kamailio 4.4.7 on that environment i will try to run some test locally simulating reception of a lot presence subscription and observe mem_copy_subs_noc(), Just to understand, both mem_copy_subs_noc are not expected to increase, is that right? What do they exactly mean? Thanks On Sat, 11 Sep 2021, 22:22 Henning Westerholt, <hw@skalatan.de<mailto:hw@skalatan.de>> wrote: Hello, the output below indicates the memory allocated in the individual functions. So it seems that the mem_copy_subs_noc() function allocates a lot of memory. It is increasing over time? The final output looks like a wrapping error, the counter goes negative. Which version of Kamailio do you use on the server? Cheers, Henning -- Henning Westerholt – https://skalatan.de/blog/ Kamailio services – https://gilawa.com<https://gilawa.com/> From: sr-users <sr-users-bounces@lists.kamailio.org<mailto:sr-users-bounces@lists.kamailio.org>> On Behalf Of Albert Petit Sent: Thursday, September 9, 2021 11:42 PM To: SIP Router - Kamailio (OpenSER) and SIP Express Router (SER) - Users Mailing List <sr-users@lists.sip-router.org<mailto:sr-users@lists.sip-router.org>> Subject: [SR-Users] Question about suspected memory leak presence module Hi, I am suspecitng presence module might be having a memory leak on a production server used by an end user (not have access to it). The output of command kamcmd mod.stats presence shm is Module: presence { mem_copy_subs(148): 25720 mem_copy_subs_noc(214): 1672201904 mem_copy_subs_noc(251): 678406560 add_event(181): 88 shm_copy_event(57): 40 shm_copy_event(50): 312 add_event(156): 40 add_event(149): 456 new_shtable(66): 5767168 new_shtable(53): 262144 init_evlist(289): 16 Total: -1938302848 } I am not sure what mem_copy_subs_noc is meaning. And final output is negative, SHM is incfreasing all the time but not sure of the root cause is this a reasonable hint that a memory leak is related to presence?