On Mon, Mar 23, 2026 at 12:52 PM Antonin Houska <ah@cybertec.at> wrote:
I hit a limitation of the isolation tester when trying to reproduce a bug in REPACK (CONCURRENTLY) [1]: it does not recognize that session is blocked due to background worker waiting on an injection point. This patch tries to fix that.
+1. I was thinking can we move the logic of checking if bg workers are the reason of blocking the main backend inside pg_isolation_test_session_is_blocked to make it cleaner, and regarding "XXX Should we use a separate query for that?" i am confused here IIUC if we keep it as 1 query using UNION every time its for sure that both the queries will run, which can increase more execution time but less libpq/socket calls, but if we send as 2 queries if 1st query doesn't returns true we have to go and check the other query, so here if 2 queries ran then execution + libpq/socket calls overhead, so i am slightly inclined towards separating the queries , so that if 1st gets satisfied then we don't touch the 2nd query at all, please correct me if i am wrong here :)
