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Subject: Re: shm
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> On Mar 5, 2020, at 7:51 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>=20
> 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=EF=BB=BF=


So something is using shared memory, and wants 1MB chunks. What could =
that be?

This is on PG 11.7