Hi!

I'm using Ozone 3.38c with a J-Link Pro under Arch Linux, installed from AUR.
Since a few versions, I noticed that Ozone starts one or more JLinkGUIServerExe processes that take 100% CPU after a short while.

What is the purpose of this process?

As a workaround, the processes can be killed with killall JLinkGUIServerExe.

Another workaround is to simply rename the JLinkGUIServerExe file:

sudo mv /opt/SEGGER/JLinkGUIServerExe{,_bak}

Surprisingly, this does not have any effect on the Ozone session..

The problem can also be reproduced using telnet:

Good case:

$ /opt/SEGGER/JLinkGUIServerExe &

$ telnet 127.0.0.1 19022
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
J-Link GUI server;V8.12b;


Bad case:

$ /opt/SEGGER/JLinkGUIServerExe &

<<< WAIT 10 seconds >>>

$ telnet 127.0.0.1 19022
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
Connection closed by foreign host.

-> JLinkGUIServerExe now takes 100% CPU.

I'll attach an strace log:

strace -o trace.txt -f /opt/SEGGER/JLink/JLinkGUIServerExe

showing a

* succesful open and close of a telnet connection (line 2545 ..)

* 10s wait (line 2665 ..)
.. it then seems to close the server socket in line 2765

* a failed telnet connection

server is now stuck in a 100% CPU loop while calling pselect6 for the already closed server socket.

trace.txt