Ejabberd Server Application CPU Overload

Question

We have build Ejabberd in AWS EC2 instance and have enabled the clustering in the 6 Ejabberd servers in Tokyo, Frankfurt, and Singapore regions. The OS, middleware, applications and settings for each EC2 instance are exactly the same.

But currently, the Ejabberd CPUs in the Frankfurt and Singapore regions are overloaded. The CPU of Ejabberd in the Japan region is normal.

Could you please tell me the suspicious part?

Answer 1

You can take a look at the ejabberd log files of the problematic (and the good) nodes, maybe you find some clue.

You can use the undocumented "ejabberdctl etop" shell command in the problematic nodes. It's similar to "top", but runs inside the erlang virtual machine that runs ejabberd

ejabberdctl etop

========================================================================================
 ejabberd@localhost                                                        16:00:12
 Load:  cpu         0               Memory:  total       44174    binary       1320
        procs     277                        processes    5667    code        20489
        runq        1                        atom          984    ets          5467

Pid            Name or Initial Func    Time    Reds  Memory    MsgQ Current Function
----------------------------------------------------------------------------------------
<9135.1252.0>  caps_requests_cache     2393       1    2816       0 gen_server:loop/7   
<9135.932.0>   mnesia_recover           480      39    2816       0 gen_server:loop/7   
<9135.1118.0>  dets:init/2               71       2    5944       0 dets:open_file_loop2
<9135.6.0>     prim_file:start/0         63       1    2608       0 prim_file:helper_loo
<9135.1164.0>  dets:init/2               56       2    4072       0 dets:open_file_loop2
<9135.818.0>   disk_log:init/2           49       2    5984       0 disk_log:loop/1     
<9135.1038.0>  ejabberd_listener:in      31       2    2840       0 prim_inet:accept0/3 
<9135.1213.0>  dets:init/2               31       2    5944       0 dets:open_file_loop2
<9135.1255.0>  dets:init/2               30       2    5944       0 dets:open_file_loop2
<9135.0.0>     init                      28       1    3912       0 init:loop/1         
========================================================================================