seiliki@xxxxxxxxxxxxx wrote:
The following listening worker thread behaves as expected if I insert/delete rows into/from table "t1" in psql prompt. My trouble is when the SQL execution worker thread inserts/ deletes rows into/from table "t1", the listening worker thread then goes crazy: PQnotifies() always returns NULL which pushes the listening thread to grab all CPU power because select() returns immediately in every iteration. The weird part is that select() says that there is something available but PQnotifies() returns NULL.
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Please ignore this question! My connection pool implementation seems to have flaw. Somehow and somewhere the connection acquired by a thread is robbed by other threads. The PGconn sending "LISTEN NotifyMe" becomes different from the PGconn passed to PQsocket(), PQconsumeInput(), and/or PQnotifies().
I was looking at it carefully, and was about to ask about the connection- in particular whether it was shared across threads etc. Glad you've found the issue, I've been caught by something very similar using list/notify on Lazarus/FPC where you can end up with several handles only one of which is reliable.
Please also pardon me for asking inappropriate questions like this one. As far as I can recall, every issue I encountered before always finally proved that PostgreSQL is flawless.
But at least it demonstrates that somebody's using that facility. -- Mark Morgan Lloyd markMLl .AT. telemetry.co .DOT. uk [Opinions above are the author's, not those of his employers or colleagues] -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
