Improve heuristic to check if PG is local about pgmetrics HOT 4 CLOSED

Added in commit 581da00.

from pgmetrics.

Yes, that sounds reasonable. I suppose changing the current query from:

SELECT COALESCE(inet_client_addr() = inet_server_addr(), TRUE)

to:

SELECT COALESCE(inet_client_addr() = inet_server_addr(), TRUE) OR (inet_server_addr() << '127.0.0.0/8')

should do the trick. What do you think?

from pgmetrics.

I wonder if there is some weird networking scenario (DNAT?) where inet_server_addr() is 127.0.0.0/8 but the client is actually connecting from outside(i.e. inet_client_addr() is not 127.0.0.0/8).
WDYT about

SELECT COALESCE(inet_client_addr() = inet_server_addr(), TRUE) OR (inet_server_addr() << '127.0.0.0/8' AND inet_client_addr() << '127.0.0.0/8')

from pgmetrics.

That should reduce the false positives. Might still fail for cases like when pgmetrics connects remotely to a pooler/proxy that in turn connects to a locally-running postgres over a localhost interface.

Anyway, last one above should be good enough as a heuristic I feel. We can always add a --force-local={true|false} or some such flag later if required.

from pgmetrics.