Problems debugging memory issues - sr-users

15 Dec 2020

Hi,

I'm trying to investigate a possible memory leak issue in Kamailio and I'm
following the instructions indicated in
https://www.kamailio.org/wiki/tutorials/troubleshooting/memory

I'm using Kamailo 4.4 with the following kamailio internals:

Print out of kamailio internals
  Version: kamailio 4.4.2 (x86_64/linux) 892ad6
  Default config:
/apollo/env/TachyonPlatformKamailio/etc/kamailio/kamailio.cfg
  Default paths to modules:
/apollo/env/TachyonPlatformKamailio/lib64/kamailio/modules
  Compile flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS,
USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP,
PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, DBG_QM_MALLOC,
USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER,
USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES
  MAX_RECV_BUFFER_SIZE=262144
  MAX_LISTEN=16
  MAX_URI_SIZE=1024
  BUF_SIZE=65535
  DEFAULT PKG_SIZE=8MB
  DEFAULT SHM_SIZE=64MB
  ADAPTIVE_WAIT_LOOPS=1024
  TCP poll methods: poll, epoll_lt, epoll_et, sigio_rt, select
  Source code revision ID: 892ad6
  Compiled with: x86_64-unknown-linux-gnu-gcc 4.9.4
  Compiled on: 23:36:48 Dec  8 2020
Thank you for flying kamailio!

I have attached to one of the kamailio tcp receiver processes via GDB and I
am trying to dump memory blocks from the memory manager.  However,
mem_block is not in the current_context.

The following is the output from my gdb session:

Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html
...
  This is free software: you are free to change
and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-amazon-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from
/opt/codedeploy-agent/deployment-root/95bb1634-e653-4cec-b327-99b18b9227a8/d-7AJ1XZP58/deployment-archive/sbin/kamailio...done.
Attaching to program: /apollo/env/TachyonPlatformKamailio/sbin/kamailio,
process 8946
ptrace: Operation not permitted.
(gdb) set $i=0
(gdb) set $a = mem_block->first_frag
No symbol "mem_block" in current context.
(gdb) info list
Undefined info command: "list".  Try "help info".
(gdb) info threads
No threads.

Is there something I need to do before accessing the mem_block symbol?

Also do you have any other suggestions for debugging memory leaks that may
not be documented?

Note: i can't upgrade to the latest version of Kamailio as we have custom
modules and would require considerable effort to upgrade.

Thanks,

Sheldon.