Supervisord behavior when receiving a SIGTERM signal

[RazorBach]

In my supervisord config, i have several processes which includes one process A that cannot exit on SIGTERM.

After supervisord received the SIGTERM signal received SIGTERM indicating exit request
I can see some of them are killed while some processes including process A are still running.

I think it's due to the one special process A b/c after i killed -9 this process A, all remaining processes are killed immediately.

Does this mean the supervisord processes the SIGTERM signal and sends it to each processes sequentially?

Should it try to send this SIGTERM parallel to each process?