> On Mar 5, 2020, at 7:51 AM, Tom Lane <tgl@xxxxxxxxxxxxx> wrote: > > We still allocate a small shm block as a means of counting live backends > (since the SysV spec includes an "nattch" count but mmap'd segments do > not provide that info). Should only be ~50 bytes though. I recreated the error so I could post it here: ERROR 53100 (disk_full) could not resize shared memory segment "/PostgreSQL.935653392" to 1048576 bytes: No space left on device So something is using shared memory, and wants 1MB chunks. What could that be? This is on PG 11.7