>On Fri, Dec 7, 2012 at 7:26 PM, Thalis Kalfigkopoulos <tkalfigo(at)gmail(dot)com> wrote:
>>On Fri, Dec 7, 2012 at 10:21 AM, Hari Babu < <mailto:haribabu.ko...@huawei.com> haribabu(dot)komm(at)huawei(dot)com> 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? >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. Usually we are using the pg_ctl with shutdown option only. Actually I thought of asking the postmaster crash scenario, which I have simulated with kill -9 PID. I know postmaster crash is a very rare scenario, In this I want to know what are all the problems can occur? Regards, Hari babu.
