Re: PostgreSQL 12 - ERROR: could not rename file "pg_logical/snapshots/1A-7C00D890.snap.13594.tmp" to "pg_logical/snapshots/1A-7C00D890.snap": No space left on device

raf <raf(at)raf(dot)org> writes:
> FOUTE K. Jaurès wrote:
>> The result of df -i
>>
>> Sys. de fichiers Inœuds IUtil. ILibre IUti% Monté sur
>> udev 3065149 433 3064716 1% /dev
>> tmpfs 3072780 665 3072115 1% /run
>> /dev/sdb2 59973632 356029 59617603 1% /
>> tmpfs 3072780 7 3072773 1% /dev/shm
>> tmpfs 3072780 10 3072770 1% /run/lock
>> tmpfs 3072780 17 3072763 1% /sys/fs/cgroup
>> /dev/sdb1 0 0 0 - /boot/efi
>> tmpfs 3072780 19 3072761 1% /run/user/108
>> tmpfs 3072780 5 3072775 1% /run/user/1001
>> tmpfs 3072780 5 3072775 1% /run/user/1000

> So that's not it. It would take ~60 million
> files to fill up your / inode table. I can't
> think of another explanation for that error
> message if df without -i also shows free space.

I'm going to take a shot in the dark and ask if the root file system
is XFS. It doesn't take too much googling to find out that XFS has a
reputation for reporting ENOSPC when there seems to be more than enough
room left. Apparently, it can do so as a result of fragmentation problems
even though the disk as a whole has lots of space --- for one cautionary
example see this thread:

https://www.spinics.net/lists/linux-xfs/msg22856.html

typo-ishly titled "ENSOPC on a 10% used disk". It looks like the XFS crew
installed a fix for the underlying bug ... but that thread is from 2018
and you're running a 2015 Ubuntu release.

Or, to cut to the chase: maybe updating to a less hoary kernel would help.
If you are stuck with this Ubuntu release for some reason, consider using
a less bleeding-edge-at-the-time file system.

regards, tom lane