Peter Geoghegan <pg@xxxxxxx> writes: > On Wed, Feb 1, 2023 at 3:02 PM Tom Lane <tgl@xxxxxxxxxxxxx> wrote: >>> 2023-01-24 02:35:45.833 PST [3424807] LOG: PID 0 in cancel request did not >>> match any process >>> *Error locking mutex 22* > I wonder if 22 might be EINVAL, which is one possible error code used > by pthread_mutex_lock(). Maybe, but we still don't know what's reporting the error. I tried searching for "Error locking mutex" in Debian Code Search, and got several hits, but none of them match this exactly --- the ones that offer any additional info present it as a string not a number. regards, tom lane