Re: Backend process is still runs even postmaster got killed

[Thalis Kalfigkopoulos <tkalfigo@xxxxxxxxx>]

On Fri, Dec 7, 2012 at 10:21 AM, Hari Babu <haribabu.kommi@xxxxxxxxxx> wrote:

Backend processes are still running even if the postmaster got killed and all other server processes are exited by checking the

Postmaster status.

 

And the backend process is providing  the service to the client.

Is there any problems are possible? If we continue the system for a long  time with the above behavior?

 

Until all these kind of backend processes are exited, postmaster is failing to start.

Manual cleanup is required for these backend processes? Or is there anyway we can handle?

 

Regards,

Hari babu.

 

Hi Hari.

 

How exactly do you kill the postmaster? It is suggested you use pg_ctl for server shutdowns/restarts. Check out the option -m:
 -m SHUTDOWN-MODE   can be "smart", "fast", or "immediate"
Shutdown modes are:
  smart       quit after all clients have disconnected
  fast        quit directly, with proper shutdown
  immediate   quit without complete shutdown; will lead to recovery on restart
 
"Smart" will wait for all your backend processes to terminate (or fail if it takes too long). If i remember correctly "fast" will cause the postmaster to exit even if backends are still up, the equivalent of sending a kill -15 (SIGTERM). And "immediate" is like sending a kill -9 (SIGKILL) i.e. violent shutdown of everything.

I'm guessing you went for the equivalent of SIGTERM that's why you still have backends running.

regards,
--thalis