ocserv-main hang and 100% cpu usage

[Jov]

This happened 2 times recently,the process is still there ,how can I
help to debug it?

ps aux:
root        28941 100.0  1.2  65660 11860  -  Rs   Sun06PM   620:16.50
ocserv: ocserv-main (ocserv)
_ocserv     19158   0.0  0.0      0     0  -  Z    12:21AM     0:00.01 <defunct>
_ocserv     19161   0.0  0.0      0     0  -  Z    12:21AM     0:00.01 <defunct>

backtrace:
(gdb) bt
#0  0x0000000801eafc23 in ev_feed_event () from /usr/local/lib/libev.so.4
#1  0x0000000801eb103a in ev_default_loop () from /usr/local/lib/libev.so.4
#2  0x0000000801eb12d9 in ev_invoke_pending () from /usr/local/lib/libev.so.4
#3  0x0000000801eb1f1b in ev_run () from /usr/local/lib/libev.so.4
#4  0x0000000000408897 in main (argc=<value optimized out>,
argv=<value optimized out>) at main.c:1434


/var/log/message:

Mar 29 00:21:11 fb ocserv[19159]: worker:  tlslib.c:475: no
certificate was found
Mar 29 00:21:11 fb ocserv[19160]: worker:  tlslib.c:475: no
certificate was found
Mar 29 00:21:11 fb ocserv[19161]: worker:  tlslib.c:475: no
certificate was found
Mar 29 00:21:11 fb ocserv[28942]: cannot load config file
/usr/local/etc/ocserv/config-per-group//super
Mar 29 00:21:14 fb kernel: tun1: link state changed to UP
Mar 29 00:21:14 fb devd: Executing '/etc/pccard_ether tun1 start'
Mar 29 00:21:21 fb ocserv[19161]: common.c:609: recvmsg: Operation timed out
Mar 29 00:21:21 fb ocserv[19161]: worker: 14.127.251.31
worker-auth.c:548: error receiving auth reply message
Mar 29 00:21:21 fb ocserv[19161]: worker: 14.127.251.31 failed cookie
authentication attempt

client:AnyConnect Android 4.0.05054

uname:
FreeBSD fb 10.3-RELEASE-p16 FreeBSD 10.3-RELEASE-p16