They are parallel processes. Likely someone is running a parallel query once and awhile. They would come and go as needed depending on how the database parameters are set. Here is a place to start reading about Parallel: http://download.oracle.com/docs/cd/B19306_01/server.102/b14231/manproc.h tm#i1010373 HTH Ric Van Dyke Hotsos Enterprises, Ltd. -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of dba1 mcc Sent: Monday, January 04, 2010 9:34 AM To: oracle-l@xxxxxxxxxxxxx Subject: too many ora_pXXX pop-up? I have ORACLE database 10.2.0.4 on Redhat AS 5.4 (X86-64). Recently I found some time there have process call "ora_pXXX_dbname" will pop up and may up to 128 processes. Those "ora_pxxx_dbanme" will disappear normally after 10 -20 minutes. Does anyone know what is "ora_pxxx_dbname"? Why it come and why it go? Why some many processes pop-up? Thanks. ======================================= oracle 4653 1 0 17:21 ? 00:00:11 ora_p000_db01 oracle 4655 1 0 17:21 ? 00:00:08 ora_p001_db01 oracle 4657 1 0 17:21 ? 00:00:08 ora_p002_db01 oracle 4659 1 0 17:21 ? 00:00:08 ora_p003_db01 oracle 4661 1 0 17:21 ? 00:00:08 ora_p004_db01 oracle 4663 1 0 17:21 ? 00:00:08 ora_p005_db01 oracle 4665 1 0 17:21 ? 00:00:09 ora_p006_db01 oracle 4667 1 0 17:21 ? 00:00:08 ora_p007_db01 oracle 4669 1 0 17:21 ? 00:00:09 ora_p008_db01 .... oracle 5851 1 0 17:36 ? 00:00:00 ora_p122_db01 oracle 5853 1 0 17:36 ? 00:00:00 ora_p123_db01 oracle 5855 1 0 17:36 ? 00:00:00 ora_p124_db01 oracle 5857 1 0 17:36 ? 00:00:00 ora_p125_db01 oracle 5859 1 0 17:36 ? 00:00:00 ora_p126_db01 oracle 5861 1 0 17:36 ? 00:00:00 ora_p127_db01 -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l