We have implemented an automated database refresh process where production database is exported using EXPDP and dump file is copied over to development environment where it is imported. From time to time we run into import failures with these messages -
ORA-39014: One or more workers have prematurely exited.
ORA-39029: worker 5 with process name "DW02" prematurely terminated
ORA-31672: Worker process DW02 died unexpectedly.
Initially we thought IMPDP process died for some reason and we restarted the IMPDP with the same dump file, but it would fail again. Only way to recover from this is to run EXPDP in production database again and use that dump file to import into development.
We suspected the copy process somehow corrupted the dump file but copying the same file over never worked.
We encrypt our export dump using EXPDP and Oracle seems to suggest that encryption may be corrupting the file intermittently, we can't remove encryption due to our backup policy, but if you are hitting this error then it is worth a try to monitor import without encrypted dump file.