Scott Marlowe escribió:
> scenario 1: There's a postmaster, it owns all the child processes.
> It gets killed. The Postmaster gets restarted. Since there isn't one
> running, it comes up.
Actually there's an additional step required at this point. There isn't
a postmaster running, but a new one refuses to start, because the shmem
segment is in use. In order for the second postmaster to start, the
sysadmin must remove the PID file by hand.
> starts new child processes. Meanwhile, the old child processes that
> don't belong to it are busy writing to the data store. Instant
> corruption.
In this scenario, it is both a kernel fault and sysadmin stupidity. The
corruption that ensues is 100% deserved.
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Alvaro Herrera http://www.CommandPrompt.com/
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