To me ie (in my environment) that means slow disks. We do a lot of daily loads with truncates, whenever we get bad disks or san troubles the truncates pile up and that's the wait message or on some boxes it just means we've hit a scalability wall with i/o -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of CRISLER, JON A Sent: Tuesday, February 07, 2012 10:57 AM To: oracle-l@xxxxxxxxxxxxx Subject: Wait Event - rdbms ipc message Oracle RAC 11g, AWR reports shoes the metric "rdbms ipc message" as the #1 in Top 5 wait events. I have to admit I don't think I have seen this before, and I am not sure where to look- 11gR2 on Red Hat Linux 5 64 bit, ASM to SAN. Any suggestions ? -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l