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@raf.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