Re: [COMMITTERS] pgsql: Add pg_terminate_backend() to allow terminating only a single

"Bruce Momjian" <bruce(at)momjian(dot)us> writes:

>> > Log Message:
>> > -----------
>> > Add pg_terminate_backend() to allow terminating only a single session.

I'm interested in this because I was already looking for a solution to the
"out of signals" problem we have.

I think we could expand this by having a bunch of boolean flags, one each for
different conditions including the sinval processing conditions, interrupt,
info, and terminate. (Any more?)

The two things we would have to check to be sure of is:

1) Do we care about how many times events are processed? Ie, if you press
interrupt twice is it important that that be handled as an interrupt twice? It
doesn't work that way currently for interrupt but are any of the other
conditions sensitive to this? I don't think so.

2) Do we care what order things happen in? Ie, if you send an info request and
then a cancel request is it ok if the cancel is handled first. I don't see why
not myself. And if it's a terminate request we *clear* don't want to bother
handling any other events first.

It seems to me we could replace all of the above with either SIGINT or USR1
and have a bunch of boolean flags in MyProc. I'm not sure of the implication
for sinval processing of having to get a whole bunch of LWLocks though.

--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com
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