Received a packet PING

Hello and congratulations for your software.
I use traccar with 100 TK102-2.
Everything worked correctly but for a few days in the logs system I have the following lines which appear continuously:

INFO   | jvm 1    | 2017/12/21 02:07:54 | WrapperManager Debug: Received a packet PING : ping 003ef54d
INFO   | jvm 1    | 2017/12/21 02:07:54 | WrapperManager Debug: Send a packet PING : ping 003ef54d
DEBUG  | wrapperp | 2017/12/21 02:07:54 | read a packet PING : ping 003ef54d
DEBUG  | wrapperp | 2017/12/21 02:07:58 | Send a packet PING : ping 003ef576
INFO   | jvm 1    | 2017/12/21 02:07:59 | WrapperManager Debug: Received a packet PING : ping 003ef576
INFO   | jvm 1    | 2017/12/21 02:07:59 | WrapperManager Debug: Send a packet PING : ping 003ef576
DEBUG  | wrapperp | 2017/12/21 02:07:59 | read a packet PING : ping 003ef576
DEBUG  | wrapperp | 2017/12/21 02:08:03 | Send a packet PING : ping 003ef59f
INFO   | jvm 1    | 2017/12/21 02:08:03 | WrapperManager Debug: Received a packet PING : ping 003ef59f
INFO   | jvm 1    | 2017/12/21 02:08:03 | WrapperManager Debug: Send a packet PING : ping 003ef59f
DEBUG  | wrapperp | 2017/12/21 02:08:03 | read a packet PING : ping 003ef59f
DEBUG  | wrapperp | 2017/12/21 02:08:07 | Send a packet PING : ping 003ef5c8
INFO   | jvm 1    | 2017/12/21 02:08:07 | WrapperManager Debug: Received a packet PING : ping 003ef5c8
INFO   | jvm 1    | 2017/12/21 02:08:07 | WrapperManager Debug: Send a packet PING : ping 003ef5c8
DEBUG  | wrapperp | 2017/12/21 02:08:07 | read a packet PING : ping 003ef5c8
DEBUG  | wrapperp | 2017/12/21 02:08:11 | Send a packet PING : ping 003ef5f1

The problem is that it saturates the disk.
So I have to erase the logs to avoid crashing the server.
An idea of what causes this?
Thanks in advance for your help.

It has something to do with YAJSW, not Traccar itself. You can try to adjust some configuration:

http://yajsw.sourceforge.net/YAJSW%20Configuration%20Parameters.html

great
thanks a lot