mtree reload commands don't remove items from memory - sr-users

18 May 2014

i started to wonder why routing was sometimes wrong in my proxy and
after studying the issue, i came to the conclusion that mtree reload
commands (mi or rpc) don't remove entries from memory when they are
removed from database.

i started my proxy with empty mtrees db table (and empty memory table):

# sip-proxy_ctl mi mt_summary
MT::  TNAME=lp_out TTYPE=0 MEMSIZE=0 NRNODES=0 NRITEMS=0 RELOADCOUNT=0
RELOADTIME=1400419785

then i added one entry to db table and gave reload command.  after that
one entry correctly showed up in memory table:

# sip-proxy_ctl mi mt_summary
MT::  TNAME=lp_out TTYPE=0 MEMSIZE=1636 NRNODES=6 NRITEMS=1 RELOADCOUNT=1
RELOADTIME=1400419817

then i deleted the only entry from db, verified with phpmyadmin that
the table really was empty, and gave again reload command.  that command
didn't have any effect in memory table:

# sip-proxy_ctl mi mt_summary
MT::  TNAME=lp_out TTYPE=0 MEMSIZE=1636 NRNODES=6 NRITEMS=1 RELOADCOUNT=1
RELOADTIME=1400419817

not even reload count got incremented.

after that i went and added some debug to rpc_mtree_reload function and
got this:

May 18 16:30:17 siika /usr/sbin/sip-proxy[26536]: INFO: mtree [mtree_mod.c:1169]:
rpc_mtree_reload(): reloading from db 'lp_out'

the info is here:

		LM_INFO("reloading from db '%.*s'\n", pt->tname.len,
pt->tname.s);
				if(mt_load_db(pt)!=0)
				{
					LM_ERR("cannot re-load mtree from database\n");	
					goto error;
				}

my conclusion is that mt_load_db() function is somehow broken.

-- juha