Обсуждение: postmaster startup time

What is the maximum time it takes for postmaster to start?

Postmaster takes some time to open it's connections, process any
WAL entries, and start accepting connections.

What's the longest time you'd expect between the execution of the
postmaster command and being able to connec?

"Steve Oualline" <soualline@stbernard.com> writes:
> What's the longest time you'd expect between the execution of the=20
> postmaster command and being able to connec?

Normal startup is a second or two on any modern hardware.  If you have
to recover from WAL, though, it could be very long.  A rule of thumb is
that it shouldn't take longer than your inter-checkpoint time
(checkpoint_timeout) ... but that's only assuming that the most recent
checkpoint attempt before the crash succeeded.  We've seen cases where
checkpoints were failing repeatedly (eg, because of out-of-space
condition on the main data partition) but the system kept merrily
spooling transactions into WAL.  In a scenario like that, there could be
a whole lot of WAL to replay :-(

            regards, tom lane