sireesha <sireesha.padmini@gmail.com> writes:
> This error is reported in Postgresql log and exact message from the log is
> below .
> 2023-01-24 02:35:45.833 PST [3424807] LOG: PID 0 in cancel request did not
> match any process
> *Error locking mutex 22*
The first of those lines comes from this bit in postmaster.c:
/* No matching backend */
ereport(LOG,
(errmsg("PID %d in cancel request did not match any process",
backendPID)));
As you can see, that would not have generated anything about a mutex.
The string "locking mutex" appears nowhere in the Postgres sources;
in fact, so far as I can find we don't use the word "mutex" in any
message whatever. So that second line is coming from something else.
Given that it's showing up in postmaster stderr, it might be coming
from libc, or from some third-party extension. But with zero context
about your system, it's hard for anyone to guess what exactly.
> Please let me know if i have to provide any other trouble report.
I take it you still didn't read the "Guide to reporting problems".
You need to err on the side of providing more information, not less.
regards, tom lane
