[OpenSIPS-Users] UDP workers consume 100% CPU

Mon Aug 12 10:54:37 EDT 2019

Hi,

Downgraded libssl to 1.0.2n-1ubuntu5.3 available in repository and still 
can reproduce this bug. You were right that this is a deadlock in 
libssl. Found TCP worker process blocked in libcrypto and a bunch of 
processes burning CPU cycles in sched_yield() waiting for the lock. 
That's really strange that do completely different libssl versions have 
such a dangerous bug. Found a few opened issues related to libssl, but 
according to comments downgrading to libssl-1.0 helped to make it stable.

> Hi,
>
> I'm using libssl-1.1.1-1ubuntu2.1~18.04.4
>
> Since I need SIP over TLS I can't just remove proto_tls. Will try to 
> reproduce it again and collect more data.
>
> On 07.08.19 13:18, Bogdan-Andrei Iancu wrote:
>> Hi Vitalii,
>>
>> As the backtraces show, it is a deadlock in TLS - if you remove the 
>> proto_tls, you will not experience this issue anymore. The root 
>> problem is not in OpenSIPS itself but in the libssl/libcrypto - what 
>> versions are you using for these libs ?
>>
>> Regards,
>>
>> Bogdan-Andrei Iancu
>>
>> OpenSIPS Founder and Developer
>>   https://www.opensips-solutions.com
>> OpenSIPS Summit 2019
>>   https://www.opensips.org/events/Summit-2019Amsterdam/
>>
>> On 08/05/2019 09:13 PM, Vitalii Aleksandrov wrote:
>>> Hi,
>>>
>>> I have a test opensips 2.4.6 (last week's checkout from 2.4 branch) 
>>> and after short load testing it started to consume all CPU resources.
>>>
>>> Here is what opensips floods to syslog:
>>> Aug  3 13:25:01 l /opensips[4774]: WARNING:core:utimer_ticker: 
>>> utimer task <tm-utimer> already scheduled for 114023190 ms (now 
>>> 176231430 ms), it may overlap..
>>> Aug  3 13:25:02 l /opensips[4774]: WARNING:core:utimer_ticker: 
>>> utimer task <tm-utimer> already scheduled for 114023190 ms (now 
>>> 176231530 ms), it may overlap..
>>> Aug  3 13:25:02 l /opensips[4774]: WARNING:core:utimer_ticker: 
>>> utimer task <tm-utimer> already scheduled for 114023190 ms (now 
>>> 176231630 ms), it may overlap..
>>> Aug  3 13:25:02 l /opensips[4774]: WARNING:core:utimer_ticker: 
>>> utimer task <tm-utimer> already scheduled for 114023190 ms (now 
>>> 176231730 ms), it may overlap..
>>> Aug  3 13:25:02 l /opensips[4774]: WARNING:core:utimer_ticker: 
>>> utimer task <tm-utimer> already scheduled for 114023190 ms (now 
>>> 176231830 ms), it may overlap..
>>> Aug  3 13:25:02 l /opensips[4774]: WARNING:core:utimer_ticker: 
>>> utimer task <tm-utimer> already scheduled for 114023190 ms (now 
>>> 176231930 ms), it may overlap..
>>> Aug  3 13:25:02 l /opensips[4774]: WARNING:core:utimer_ticker: 
>>> utimer task <tm-utimer> already scheduled for 114023190 ms (now 
>>> 176232030 ms), it may overlap..
>>> Aug  3 13:25:02 l /opensips[4774]: WARNING:core:timer_ticker: timer 
>>> task <tm-timer> already scheduled for 114023090 ms (now 176232030 
>>> ms), it may overlap..
>>>
>>> Where 4774 is: "Process::  ID=7 PID=4774 Type=timer"
>>>
>>> Here is the TOP output for time consuming processes:
>>>   PID USER         PR  NI    VIRT    RES      SHR    S  %CPU 
>>> %MEM     TIME+ COMMAND
>>>  4801 opensips  20   0  721040  28496  24240 R  52.9  0.7 1817:08 
>>> opensips
>>>  4802 opensips  20   0  721040  27724  23588 R  47.1  0.7 1813:06 
>>> opensips
>>>  4806 opensips  20   0  721040  27640  23532 R  47.1  0.7 1814:41 
>>> opensips
>>>  4833 opensips  20   0  721040  28848  24812 R  47.1  0.7 1815:16 
>>> opensips
>>>  4803 opensips  20   0  721044  27928  23732 R  41.2  0.7 1817:09 
>>> opensips
>>>  4804 opensips  20   0  721040  28188  23996 R  41.2  0.7 1816:05 
>>> opensips
>>>  4799 opensips  20   0  721040  28272  24172 R  35.3  0.7 1813:29 
>>> opensips
>>>  4800 opensips  20   0  721040  28340  24204 R  29.4  0.7 1816:52 
>>> opensips
>>>  4805 opensips  20   0  723256  29620  25300 R  29.4  0.8 1819:28 
>>> opensips
>>>
>>> And here is the "opensipsctl ps" for them:
>>> Process::  ID=32 PID=4799 Type=SIP receiver udp:127.0.0.1:5070
>>> Process::  ID=33 PID=4800 Type=SIP receiver udp:127.0.0.1:5070
>>> Process::  ID=34 PID=4801 Type=SIP receiver udp:127.0.0.1:5070
>>> Process::  ID=35 PID=4802 Type=SIP receiver udp:127.0.0.1:5070
>>> Process::  ID=36 PID=4803 Type=SIP receiver udp:127.0.0.1:5070
>>> Process::  ID=37 PID=4804 Type=SIP receiver udp:127.0.0.1:5070
>>> Process::  ID=38 PID=4805 Type=SIP receiver udp:127.0.0.1:5070
>>> Process::  ID=39 PID=4806 Type=SIP receiver udp:127.0.0.1:5070
>>> Process::  ID=66 PID=4833 Type=TCP receiver
>>>
>>> "strace" output for those burning processes just floods with:
>>> 11:07:04.042794 sched_yield()           = 0
>>> 11:07:04.042869 sched_yield()           = 0
>>> 11:07:04.042943 sched_yield()           = 0
>>> 11:07:04.043016 sched_yield()           = 0
>>> 11:07:04.043090 sched_yield()           = 0
>>> 11:07:04.043164 sched_yield()           = 0
>>>
>>> Unfortunately this opensips is striped and gdb output is limited.
>>> GDB bt of TCP receiver:
>>> (gdb) bt
>>> #0  0x00007f939211fe57 in sched_yield () at 
>>> ../sysdeps/unix/syscall-template.S:78
>>> #1  0x00007f936fffc14d in ?? () from 
>>> /usr/lib/x86_64-linux-gnu/opensips/modules/proto_tls.so
>>> #2  0x00007f93791698d5 in send_pr_buffer () from 
>>> /usr/lib/x86_64-linux-gnu/opensips/modules/tm.so
>>> #3  0x00007f93791626b8 in relay_reply () from 
>>> /usr/lib/x86_64-linux-gnu/opensips/modules/tm.so
>>> #4  0x00007f937919fe2a in timer_routine () from 
>>> /usr/lib/x86_64-linux-gnu/opensips/modules/tm.so
>>> #5  0x000055e00034a58a in handle_timer_job ()
>>> #6  0x000055e00041ae2a in tcp_worker_proc_loop ()
>>> #7  0x000055e000427218 in tcp_start_processes ()
>>> #8  0x000055e0002e6837 in main ()
>>>
>>> GDB bt of UDP receiver:
>>> #0  0x00007f939211fe57 in sched_yield () at 
>>> ../sysdeps/unix/syscall-template.S:78
>>> #1  0x00007f936fffc14d in ?? () from 
>>> /usr/lib/x86_64-linux-gnu/opensips/modules/proto_tls.so
>>> #2  0x00007f93791698d5 in send_pr_buffer () from 
>>> /usr/lib/x86_64-linux-gnu/opensips/modules/tm.so
>>> #3  0x00007f93791626b8 in relay_reply () from 
>>> /usr/lib/x86_64-linux-gnu/opensips/modules/tm.so
>>> #4  0x00007f9379165015 in reply_received () from 
>>> /usr/lib/x86_64-linux-gnu/opensips/modules/tm.so
>>> #5  0x000055e000322fed in forward_reply ()
>>> #6  0x000055e000309d1d in receive_msg ()
>>> #7  0x000055e00042b4be in ?? ()
>>> #8  0x000055e000413dd8 in udp_start_processes ()
>>> #9  0x000055e0002e6724 in main ()
>>>
>>> Those workers don't process any incoming SIP messages and just stay 
>>> in this infinite loop.
>>>
>>> Any input is very appreciated.
>>>
>>>
>>> _______________________________________________
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>>> http://lists.opensips.org/cgi-bin/mailman/listinfo/users
>>