PG::TRDeadlockDetected: ERROR: deadlock detected

Build Environment Databases
1

Has anyone else experienced this error when specs are run on CircleCI?

PG::TRDeadlockDetected: ERROR: deadlock detected

It goes on to say…

DETAIL:  Process 11443 waits for AccessShareLock on relation 16956 of database 16634; blocked by process 11330.
   Process 11330 waits for AccessExclusiveLock on relation 17200 of database 16634; blocked by process 11443.
   HINT:  See server log for query details.
   : SELECT COUNT(DISTINCT "units"."id") FROM "units" LEFT OUTER JOIN "unit_meta_data" ON "unit_meta_data"."unit_id" = "units"."id" LEFT OUTER JOIN "locations" ON "locations"."id" = "units"."location_id" LEFT OUTER JOIN "unit_photos" ON "unit_photos"."unit_id" = "units"."id" WHERE "units"."owner_id" = $1

I’m leaving my query in, incase it provide some sort of insight. This doesn’t seem to occur in production or any other environment, just semi-periodically when tests are run.

2

A deadlock usually happens when a table is not available due to some other query blocking it, what are the previous few queries that are run in your testing suite?

3

Yes, I’m running into the same issue with a host of different queries in a Rails app during Capybara feature specs.