Re: BUG #16817: kill process cause postmaster hang

PG Bug reporting form <noreply@postgresql.org> writes:
>     Recently we encountered a problem that after killed walwriter, we expect
> the database can recover normally, but it not (the postmaster hang in the
> stat of  'wait dead end', and the archiver does't exit).
>     After analysis this problem, we found it could be a bug for a long time.
> for archiver now use 'system' to call the configed archive command. For
> 'system' the linux programmer's manual describe the following 'During
> execution of the command, SIGCHLD will be blocked, and SIGINT and SIGQUIT
> will be ignored'. 

>     So, when a child chrash, we now just SIGQUIT the archiver just one time,
> while the archiver just execute 'system', SIGQUIT  will be ignored, then the
> posmaster hang in stat of 'wait dead end'.

Not sure I believe this: why wouldn't the SIGKILL-after-5-seconds logic
get us out of that situation?

            regards, tom lane