What to do About "sendKillCmdToWatchdog"

You may ignore SendKillCmdToWatchdog, if you see it in your error log, like so:

2019-04-22 20:35:30.124450 NOTICE [2348767] Cmd from child: [extappkill:2348876:-3:0]
2019-04-22 20:35:36.113564 NOTICE [2348803] sendKillCmdToWatchdog: 'extappkill:2349000:-3:0'.
2019-04-22 20:35:36.113670 NOTICE [2348767] Cmd from child: [extappkill:2349000:-3:0]
2019-04-22 20:35:36.293086 NOTICE [2348803] sendKillCmdToWatchdog: 'extappkill:2349042:-3:0'.

It does not indicate any trouble.

If you'd like to supress sendKillCmdToWatchdog messages, simply set the log level to WARNING.