Re: pg_restore cancel TODO

On Mon, Oct 19, 2015 at 09:26:21AM -0700, Jeff Janes wrote:
> It seems like gdb eats signals that you send a process while it is being
> debugged, so it is hard to figure out what is going on.  From strace, it looks
> like the children do receive a signal but either ignore it, or set a flag and
> then ignore that.
>
> It doesn't continue to load the entire dump file, it exits once they complete
> the current assignment and ask the parent for more work.
>
> Could just be a matter of adding the local equivalent of CHECK_FOR_INTERRUPTS
> in the part of the code that spools COPY data to the backends?  I'm not sure
> what would happen if it were in the index/constraint building phase, I've never
> let it get that far when it reported errors early on.
>
> (This is linux, sorry for not making that clear)

Well, we are not running COPY in pg_upgrade, just the DDL commands.
Index creation is on empty tables, so it should be very quick.  What
should basically happen is that the pg_restore child processes should
exit as forked children, and then the backends for these pg_restore
proceses should then exit.  My guess is that this problem is not
pg_upgrade-specific as there is no signal control in pg_upgrade --- you
are just getting the defaults.

(Updated TODO to mention Linux.)