Thresholds trigger advice contained in Rules member IODRUEXC.
Sometimes the advice is very specific and points to an immediate solution:
Example
ADVICE: The number of parallel groups did not reach the planned level due
to buffer pool limitations. Increase the size of the buffer pool in which
objects accessed by this statement reside.
In other cases, the advice might suggest additional research paths:
Example
ADVICE: This execution spent a high percentage of time waiting on locks or
latches. You can use EXPLAIN to determine the locking characteristics of
this statement; you can get details on locking activity with BMC AMI Ops Monitor for Db2.
The following examples show a rule and the corresponding advice that Exception Advisor issued after a threshold was surpassed:
Rule example
Example
RULE:SyncIOWait percentage;PERCENTAGE=SYNCWAIT/ELAPTIME; > 30
This execution spent a large percentage of time performing
synchronous I/Os. If the getpage count has risen, it can indicate
a need to rebind the program, update catalog statistics for accessed
objects, or reorganize affected objects. Also check for RID list
failures for the statement and buffer pool performance for accessed
objects.
*
Example
*ADVICE:This execution spent a large percentage of time performing
synchronous I/Os. If the getpage count has risen, it can indicate a need
to rebind the program, update catalog statistics for accessed objects, or
reorganize affected objects. Also check for RID list failures for the
statement and buffer pool performance for accessed objects.