[SR-Users] S-CSCF can not allocate memory

Hello, I haved install debian 8 and kamailio 4.4.7 for IMS testing. After registering 10000 users, SIPp generates CPS 25 SIP INVITE message and BYE message after 100 seconds. After about 240000 calls, there are "cannot allocate memory" messgae on S-CSCF. The command of S-CSCF is "kamailio -m 512 -f /etc/scscf/kamailio.cfg" The parameter mem_join=1 is included in kamailio.cfg. I have modified the share memory to 1024 and 2048, but the result is the same, just increasing the pass calls. Would you please tell me how to solve the memory problem? Thanks. Mar 21 12:25:03 Kamailio440 kamailio[16483]: ERROR: <core> [sip_msg_clone.c:981]: msg_lump_cloner(): cannot allocate memory Mar 21 12:25:03 Kamailio440 kamailio[16483]: ERROR: tm [t_fwd.c:1656]: t_forward_nonack(): ERROR: t_forward_nonack: failed to save the message lumps Mar 21 12:25:03 Kamailio440 kamailio[16483]: ERROR: tm [t_reply.c:545]: _reply_light(): ERROR: _reply_light: cannot allocate shmem buffer Mar 21 12:25:03 Kamailio440 kamailio[16483]: ERROR: tm [t_lookup.c:1489]: t_unref(): ERROR: t_unref: generation of a delayed stateful reply failed Mar 21 12:25:03 Kamailio440 kamailio[16446]: ERROR: tm [t_reply.c:1893]: relay_reply(): ERROR: relay_reply: cannot alloc reply shmem Mar 21 12:25:03 Kamailio440 kamailio[16446]: ERROR: tm [t_reply.c:545]: _reply_light(): ERROR: _reply_light: cannot allocate shmem buffer Mar 21 12:25:03 Kamailio440 kamailio[16435]: ERROR: tm [t_reply.c:316]: update_totag_set(): ERROR: update_totag_set: no memory Mar 21 12:25:03 Kamailio440 kamailio[16406]: ERROR: ims_dialog [dlg_profile.c:472]: set_dlg_profile(): no more shm memory Mar 21 12:25:03 Kamailio440 kamailio[16406]: ERROR: ims_dialog [ims_dialog.c:619]: w_set_dlg_profile(): failed to set profile Mar 21 12:25:03 Kamailio440 kamailio[16406]: ERROR: tm [t_lookup.c:1289]: new_t(): ERROR: new_t: out of mem: Mar 21 12:25:03 Kamailio440 kamailio[16406]: ERROR: tm [t_lookup.c:1429]: t_newtran(): ERROR: t_newtran: new_t failed root@Kamailio440:~# kamcmd tm.stats { current: 69 waiting: 0 total: 991300 total_local: 0 rpl_received: 2183891 rpl_generated: 20232 rpl_sent: 1475856 6xx: 0 5xx: 2704 4xx: 10124 3xx: 0 2xx: 978329 created: 991300 freed: 991231 delayed_free: 0 } root@Kamailio440:~# kamctl stats shmem shmem:fragments = 1630 shmem:free_size = 4303040 shmem:max_used_size = 536870912 shmem:real_used_size = 532567872 shmem:total_size = 536870912 shmem:used_size = 415668000