"CN" <cnliou9(at)fastmail(dot)fm> writes:
> LOG: server process (pid 1625) was terminated by signal 11
Definitely a backend crash ...
>> Can you get a stack backtrace from the core dump?
> I don't know how to do that! ^.^
See our mail list archives for previous explanations, but basically
1. find the "core" file at $PGDATA/base/yourdbnum/core (if not there,
restart postmaster with "ulimit -c unlimited" context and cause problem
again).
2. gdb /path/to/postgres /path/to/core
bt
quit
regards, tom lane