Re: BUG #4522: autovacuum working send SIGUSR1 to the wrong pid

Heikki Linnakangas escribió:
> Zou Yong wrote:

>> I was running postgres on a Linux with busybox. The autovacuum feature is
>> turned on. I noticed that the autovacuum worker sent SIGUSR1 to pid 1 which
>> is the init process and caused the system halt.
>
> Hmm. The postgres user shouldn't have permission to halt the system,
> methinks.

Yeah, the reason this hasn't ever been seen is that normally we don't
have permissions to signal init.  My guess is that Zou Yang is running a
system without users where everything runs as root.  This fits the fact
that it's running busybox: I guess it's an embedded system of some sort.

>> I did some debugging and found that the root cause is the constant
>> AutoVacNumSignals is not defined correctly. It should be (AutoVacRebalance +
>> 1).
>
> Yeah, that's clearly a bug. Fixed, thanks.

My fault.  Thanks for the patch.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.