Hello,

On 12.01.18 11:48, Sebastian Damm wrote:

Hi Daniel,

unless there is a silent exit from some module (those extra routes just write some information into redis), I can't find any other drop and exits than the one in the route posted. 

We have added some logging around the lock functions, and although we are missing some log lines for some packets, making it look like some locks don't get released, we do see that another PID can successfully lock the same key later.

There is no other lock/unlock in the config.

Is there a way to debug the lock array?

attaching with gdb and looking at the values is always an option. Otherwise, I do not recall anything for this purpose written in kamailio.

One guess could be that the lock array is full, although we already have the lock size set to 10.

Lock array cannot become "full", if you thought like that if there are 10 lock operations with different keys on an array of 10 locks.

Actually many string keys can use same lock/mutex -- a hashing function is performed over the key value results in an integer value which then is made modulo number of locks and the lock at that index is chosen from the array. So if you do lock("abc") and then you don't release it, then lock("xyz") can get blocked. Also, doing unlock("xyz") without lock("xyz") is releasing the lock("abc") -- note that "abc" and "xyz" are just random example to explain what can happen, but does not mean it happens for these keys.

Cheers,
Daniel

Regards,

Sebastian

On Fri, Jan 12, 2018 at 11:08 AM, Daniel-Constantin Mierla <miconda@gmail.com> wrote:

Hello,

have you checked that any of the route blocks used in between lock() and unlock() don't do an exit/drop (also not return 0)?

Do you have other lock() / unlock() in the config?

Cheers,
Daniel

On 12.01.18 08:49, Sebastian Damm wrote:

Hi,

this morning, two Kamailio servers suddenly stopped working after having worked without a problem for months. Both are running 5.0.2 on Debian Jessie. Those systems only analyze mirrored traffic and write some information to a RabbitMQ.

I tried restarting, but after a few seconds they get stuck the same way as before. Then I attached a gdb to some of the UDP listeners, and they all look pretty much the same.

===========8< process 1 =================

(gdb) bt

#0  0x00007f404ca435b9 in syscall () from /lib/x86_64-linux-gnu/libc.so.6

#1  0x00007f4049f41260 in futex_get (lock=0x7f4041bccd00) at ../../core/parser/../mem/../futexlock.h:108

#2  0x00007f4049f477d7 in cfg_lock_helper (lkey=0x7fff3c048650, mode=0) at cfgutils.c:667

#3  0x00007f4049f481ed in w_cfg_lock_wrapper (msg=0x7f404ba17f18, key=0x7f404ba15488, mode=0) at cfgutils.c:712

#4  0x00007f4049f4823c in w_cfg_lock (msg=0x7f404ba17f18, key=0x7f404ba15488 "\210a\241K@\177", s2=0x0) at cfgutils.c:717

#5  0x000000000045cd85 in do_action (h=0x7fff3c049410, a=0x7f404b9d5170, msg=0x7f404ba17f18) at core/action.c:1060

#6  0x0000000000469afa in run_actions (h=0x7fff3c049410, a=0x7f404b9d5170, msg=0x7f404ba17f18) at core/action.c:1552

#7  0x000000000045958d in do_action (h=0x7fff3c049410, a=0x7f404b9ce558, msg=0x7f404ba17f18) at core/action.c:678

#8  0x0000000000469afa in run_actions (h=0x7fff3c049410, a=0x7f404b9cdf70, msg=0x7f404ba17f18) at core/action.c:1552

#9  0x000000000046a2bd in run_top_route (a=0x7f404b9cdf70, msg=0x7f404ba17f18, c=0x0) at core/action.c:1641

#10 0x0000000000580033 in receive_msg (

    buf=0xa393f9 <buf+121> "REGISTER sip:domain SIP/2.0\r\nVia: SIP/2.0/UDP 1.2.3.4;branch=z9hG4bKfc98.c762d7151f110c7eb71fc7d4e0648f1f.0\r\nVia: SIP/2.0/UDP 192.168.0.3:5060;rport=38020;received=62.30.8.128;branch=z9hG4"...,

    len=799, rcv_info=0x7fff3c049810) at core/receive.c:264

#11 0x00007f40483efcdf in parsing_hepv3_message (buf=0xa39380 <buf> "HEP3\003\230", len=920) at hep.c:499

#12 0x00007f40483ee264 in hepv3_received (buf=0xa39380 <buf> "HEP3\003\230", len=920, ri=0x7fff3c049a50) at hep.c:231

#13 0x00007f40483ec9cb in hep_msg_received (data=0x7fff3c049a30) at hep.c:85

#14 0x000000000049e4e1 in sr_event_exec (type=7, data=0x7fff3c049a30) at core/events.c:263

#15 0x000000000048731a in udp_rcv_loop () at core/udp_server.c:466

#16 0x0000000000422d08 in main_loop () at main.c:1623

#17 0x000000000042a408 in main (argc=13, argv=0x7fff3c049ef8) at main.c:2643

(gdb) quit

===========8< process 1 =================

===========8< process 2 =================

(gdb) bt

#0  0x00007f404ca435b9 in syscall () from /lib/x86_64-linux-gnu/libc.so.6

#1  0x00007f4049f41260 in futex_get (lock=0x7f4041bccd00) at ../../core/parser/../mem/../futexlock.h:108

#2  0x00007f4049f477d7 in cfg_lock_helper (lkey=0x7fff3c048650, mode=0) at cfgutils.c:667

#3  0x00007f4049f481ed in w_cfg_lock_wrapper (msg=0x7f404ba17f18, key=0x7f404ba15488, mode=0) at cfgutils.c:712

#4  0x00007f4049f4823c in w_cfg_lock (msg=0x7f404ba17f18, key=0x7f404ba15488 "\210a\241K@\177", s2=0x0) at cfgutils.c:717

#5  0x000000000045cd85 in do_action (h=0x7fff3c049600, a=0x7f404b9d5170, msg=0x7f404ba17f18) at core/action.c:1060

#6  0x0000000000469afa in run_actions (h=0x7fff3c049600, a=0x7f404b9d5170, msg=0x7f404ba17f18) at core/action.c:1552

#7  0x000000000045958d in do_action (h=0x7fff3c049600, a=0x7f404b9cf920, msg=0x7f404ba17f18) at core/action.c:678

#8  0x0000000000469afa in run_actions (h=0x7fff3c049600, a=0x7f404b9ce9c0, msg=0x7f404ba17f18) at core/action.c:1552

#9  0x000000000046a2bd in run_top_route (a=0x7f404b9ce9c0, msg=0x7f404ba17f18, c=0x7fff3c049600) at core/action.c:1641

#10 0x0000000000580a69 in receive_msg (

    buf=0xa393f9 <buf+121> "SIP/2.0 200 OK\r\nVia: SIP/2.0/UDP 172.20.40.8;branch=z9hG4bKa69c.5cca5a54c4d270c515eeb4bbb5e0bb44.0\r\nVia: SIP/2.0/UDP 2.3.4.5:5060\r\nContact: <sip:1234567@9.8.7.6:59669;transport=UDP>\r\nTo: "..., len=506, rcv_info=0x7fff3c049810) at core/receive.c:327

#11 0x00007f40483efcdf in parsing_hepv3_message (buf=0xa39380 <buf> "HEP3\002s", len=627) at hep.c:499

#12 0x00007f40483ee264 in hepv3_received (buf=0xa39380 <buf> "HEP3\002s", len=627, ri=0x7fff3c049a50) at hep.c:231

#13 0x00007f40483ec9cb in hep_msg_received (data=0x7fff3c049a30) at hep.c:85

#14 0x000000000049e4e1 in sr_event_exec (type=7, data=0x7fff3c049a30) at core/events.c:263

#15 0x000000000048731a in udp_rcv_loop () at core/udp_server.c:466

#16 0x0000000000422d08 in main_loop () at main.c:1623

#17 0x000000000042a408 in main (argc=13, argv=0x7fff3c049ef8) at main.c:2643

(gdb) quit

===========8< process 2 =================

Looks to me as if Kamailio gets stuck trying to get a lock for this packet. 

The config file when handling those packets looks like this:

request_route {

        route(initialize_variables);

        route(foo);

}

onreply_route {

        route(initialize_variables);

        route(foo);

}

route[initialize_variables] {

        $vn(bar) = $null;

        $vn(baz) = $null;

        $vn(barbaz) = $null;

        $vn(foobar) = $null;

}

route[foo] {

        lock("$ci");

        xlog("L_DBG", "Obtained lock, calling lua...\n");

        if(!lua_run("handle_packet")) {

                xlog("L_ERR", "SCRIPT: failed to execute lua function!\n");

        }

        if ($vn(bar) != $null) {

          route(mediaIpToRedis);

        }

        if ($vn(baz) != $null) {

          route(channelInfoToRedis);

        }

        if ($vn(barbaz) != $null) {

                route(sendToQueue);

        }

        xlog("L_DBG", "All finished, releasing lock...\n");

        unlock("$ci");

        xlog("L_DBG", "Released lock...\n");

        # update stats

        if ($vn(foobar) != $null) {

                update_stat("$vn(foobar)", "+1");

        }

        drop;

        exit;

}

Is there any race condition I am missing? Until this morning, it ran without problems and only every 2 minutes or so, 4 packets were sent to the RabbitMQ. So the system throws away nearly 100% of the traffic (which is around 20 Mbit). 

In the log file, there are no errors at all, no aborted lua scripts or whatsoever.

Does anybody have a hint for me? Thanks in advance.

Regards

Sebastian

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-- 
Daniel-Constantin Mierla
www.twitter.com/miconda -- www.linkedin.com/in/miconda
Kamailio Advanced Training - March 5-7, 2018, Berlin - www.asipto.com
Kamailio World Conference - May 14-16, 2018 - www.kamailioworld.com

_______________________________________________
Kamailio (SER) - Users Mailing List
sr-users@lists.kamailio.org
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-- 
Daniel-Constantin Mierla
www.twitter.com/miconda -- www.linkedin.com/in/miconda
Kamailio Advanced Training - March 5-7, 2018, Berlin - www.asipto.com
Kamailio World Conference - May 14-16, 2018 - www.kamailioworld.com

_______________________________________________
Kamailio (SER) - Users Mailing List
sr-users@lists.kamailio.org
https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users