VCSIPC Wait Warning Messages in Oracle Trace/Log Files

When Gigabit Ethernet interconnections are used, a high load can cause LMX/LLT to flow-control VCSIPC, resulting in warning messages to be reported in the Oracle trace file. The default location for the trace file is $ORACLE_HOME/rdbms/log; it may have changed if the parameters background_dump_dest or user_dump_dest have been changed. The messages resemble:

As a workaround, you can change the LLT lowwater mark, highwater mark, and window values for flow control. Please contact VERITAS support for more information about changing these values.

VCSIPC Errors in Oracle Trace/Log Files

If you see any VCSIPC errors in the Oracle trace/log files, check /var/adm/messages for any LMX error messages. If you see messages that contain any of the following:

Refer to Tunable Kernel Driver Parameters.

If you see any VCSIPC warning messages in Oracle trace/log files that resemble:

or,

check whether the Oracle Real Application Cluster instance on the other node is still running or has been restarted. The warning message indicates that the VCSIPC/LMX connection is no longer valid.