Performance Tuning Guide - EMC Community Network

Designing Reports
missed report data. For example, if a query issued at 1:20:00 retrieves events with time stamps from
1:19:25-1:19:30, but those events do not arrive in the audit trail database until 1:19:45 (a 45-second
latency), the BAM query misses them. Subsequent BAM queries look for events with different time
stamps, so BAM never reports on the late arriving event data.
The 30-second default data transfer latency can be changed to accommodate longer latencies in
production environments. Use Documentum application system performance metrics to derive
system latencies so that you can configure the data transfer latency appropriately. Use TaskSpace to
configure the data transfer latency.
Note: Longer configured data transfer latencies, while ensuring completeness of monitored data,
result in longer delays for updated report data.
Increasing the BAM server step size
Every 5 seconds the BAM server runs the event pipe job that extracts data from the audit trail
database and inserts it into the BAM database. This five-second interval is the step size, and can be
adjusted in high volume environments.
Although there is no absolute definition, 500 events or more per minute is considered high volume.
Increasing the step size enhances performance in two ways:
• Although the BAM server runs the event pipe job less frequently, the job runs longer and more
efficiently.
• Since the job is running less frequently, the size of each transaction is larger than for a step size of 5
seconds. Larger transaction sizes also make the BAM server operate more efficiently.
The BAM server step size can be adjusted to any time period by substituting a value for "60" in the
following query. The following procedure increases the BAM server step size to 1 minute.
1. Shut down the BAM server.
2. Run the following query on the BAM database:
I_BAM_SERVER_CONFIG SET SCHEDULEPERIOD = 60 WHERE SERVERNAME = 'DCTMServer'
3. Restart the BAM server.
Understanding server clock synchronization
The Content Server, BAM application server, and BAM database server clocks must be synchronized
to within 5 seconds, with an outer limit of 30 seconds. In clustered environments the clocks between
each Content Server within the cluster must be synchronized. Lack of synchronization can result
is loss of BAM data.
Note: The BAM server clock synchronizes itself with the Content Server clock by reading the
timestamps of monitored data in the audit trail database.
EMC Documentum xCP 1.0 Performance Tuning Guide 59