there was a report in #postgresql recently about a crash on Google Cloud SQL with the somewhat misleading message "could not write to log file" while in fact it was the xlog/wal:
|PANIC: could not write to log file 000000010000019600000054 at offset | 13279232, length 245760: Cannot allocate memory |ERROR: could not write block 74666 in file "base/18031/48587": Cannot | allocate memory |CONTEXT: writing block 74666 of relation base/18031/48587 |LOG: server process (PID 5160) was terminated by signal 9: Killed
I suggest to reword that message, e.g. "could not write to transaction log file" or "could not write to wal file".
Given the change xlog -> wal, I would suggest "could not write to wal file" as the correct option there.
And +1 for rewording it. I think there are also some other messages like it that needs to be changed, and also things like
(errmsg("restored log file \"%s\" from archive"
could do with an update.
Also, the errno (ENOMEM) is curious (and the user wrote that Google monitoring reported memory at 16/20GB at the time of the crash), but it could be a due to running on a cloud-fork? As you have no access to PGDATA, it sounds difficult to diagnose after the fact.
Yeah, nobody knows what Google has done in their fork *or* how they actually measure those things, so without a repro I think that's hard..
