Autovacuum launcher doesn't notice death of postmaster immediately

I notice that in 8.3, when I kill the postmaster process with SIGKILL or 
SIGSEGV, the child processes writer and stats collector go away 
immediately, but the autovacuum launcher hangs around for up to a 
minute.  (I suppose this has to do with the periodic wakeups?).  When 
you try to restart the postmaster before that it fails with a complaint 
that someone is still attached to the shared memory segment.

These are obviously not normal modes of operation, but I fear that this 
could cause some problems with people's control scripts of the 
sort, "it crashed, let's try to restart it".

-- 
Peter Eisentraut
http://developer.postgresql.org/~petere/