PostgreSQL temporary files

Hello Commvault Community,

On one of the PostgreSQL agents, a full backup job ends with a status of ‘Completed with errors’.

PostGresBackupChild.log

30386 76b9 04/14 21:02:05 454909 ConnectGroupInternal: setsockopt failed. Error [0xECCC005F:{CQiSocket::SetSockOpt(567)/ErrNo.95.(Operation not supported)}]
30386 76b2 04/14 21:02:06 454909 ClBackupFile::OpenFilesForBackup(7033) - failed to stat path '/pgdbs/ksef/pgdata/tablespaces/ksef_data/PG_14_202107181/16389/pg_internal.init', errno=2, error=No such file or directory
30386 76b2 04/14 21:02:06 454909 ClBackupFile::UseIndexForFailedFiles(13358) - Will not store failed file information in index as this is not a file system backup. 
30386 76b2 04/14 21:02:06 454909 ClBackupFile::OpenFilesForBackup(7601) - 1 files in a row failed to be backed up.
30386 76b2 04/14 21:02:06 454909 ClBackupFile::OpenFilesForBackup(7033) - failed to stat path '/pgdbs/ksef/pgdata/tablespaces/ksef_data/PG_14_202107181/16389/t21_900557245', errno=2, error=No such file or directory
30386 76b2 04/14 21:02:06 454909 ClBackupFile::OpenFilesForBackup(7033) - failed to stat path '/pgdbs/ksef/pgdata/tablespaces/ksef_data/PG_14_202107181/16389/t21_900557248', errno=2, error=No such file or directory
30386 76b2 04/14 21:02:06 454909 ClBackupFile::OpenFilesForBackup(7033) - failed to stat path '/pgdbs/ksef/pgdata/tablespaces/ksef_data/PG_14_202107181/16389/t21_900557249', errno=2, error=No such file or directory
30386 76b2 04/14 21:02:06 454909 ClBackupFile::OpenFilesForBackup(7601) - 3 files in a row failed to be backed up.

I have searched the documentation, but it is not specified what exactly Commvault considers to be temporary files.

"„You can ignore more files during a backup operation by creating the sPGDirIgnoreList additional setting and setting its value as the name of files or folders in a comma separated list that you want to ignore.” - is not specified here too.

https://documentation.commvault.com/additionalsetting/details?name=%22sPGDirIgnoreList%22&ids21

I have two questions. What exactly does Commvault consider to be temporary files? Whether there is a list of these files?

"Each table and index is stored in a separate file. For ordinary relations, these files are named after the table or index’s filenode number, which can be found in pg_class.relfilenode. But for temporary relations, the file name is of the form tBBB_FFF, where BBB is the backend ID of the backend which created the file, and FFF is the filenode number."

https://www.postgresql.org/docs/current/storage-file-layout.html

Regards,
Michał