During the application of a help patch which was running FNDGFU concurrent requests the worker FAILED and following error was logged in .req file:
APP-FND-01564: ORACLE error 1000 in close_server_files
Cause: close_server_files failed due to ORA-01000: maximum open cursors exceeded.
The SQL statement being executed at the time of the error was: "&SQLSTMT and was executed from the file &ERRFILE".
ORACLE error 3114 in afpexcp
Cause: afpexcp failed due to ORA-03114: not connected to ORACLE.
The SQL statement being executed at the time of the error was: and was executed from the file .
After some research on metalink, I realized that the DBAs had not set INBOUND_CONNECT_TIMEOUT parameter in listener.ora, and the requests were simply timing out. After setting this parameter and setting its value to zero (for patching only), the patch proceeded without issues.
An offshoot of this error was ORA-07445 in alert log:
ORA-07445: exception encountered: core dump [drumcmf()+184] [SIGSEGV] [Address
not mapped to object] [0x000000000]  
So in 10.2.0.3, do not forget to set INBOUND_CONNECT_TIMEOUT to zero during patching and do not forget to set it back to 60, 120 or 240 whichever works best in your environment.
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