Compaq AAR-88LB-TE - Manual (Page 37)

7
Performance Tips
With RTR Version 3, there are several considerations for improving performance.
These are described in the following sections.
7.1 Process Quotas
OpenVMS process quotas should be increased to accomodate the use of mailboxes
for processes. Check the RTR Installation Guide for the specific formula to use.
7.2 Journal Sizing
With RTR, the larger the journal, the more time it takes to read it. This can
affect failover in some circumstances. Due to the new journal format, journal
files need to be created larger than in RTR Version 2 to accomodate the larger
transaction identification implemented for RTR Version 3. Monitor the journal
file periodically to make it the most effective size for your RTR environment.
7.3 RTR Startup Qualifiers
RTR startup qualifiers have changed. You no longer provide specific configuration
information, but use OpenVMS quotas; RTR Version 3 manages configuration
requirements.
7.4 Monitoring
Monitoring is an important tool for evaluating performance on RTR facilities and
between RTR nodes. It provides you with direct feedback on the performance and
characteristics of your RTR system and its applications.
Additionally, because RTR Version 3 monitoring uses RTRACP heavily,
doing constant monitoring can affect performance. If monitoring is affecting
performance on your RTR system, use a longer monitoring interval than
the default (2 seconds). Use the RTR MONITOR command with the
/INTERVAL=seconds qualifier to increase the monitoring interval.
You generally use a different monitoring interval when debugging a new
environment, facility, or application than when you are in production. This is not
different between RTR Version 2 and RTR Version 3.
7.5 Memory
RTR Version 3 requires more memory than RTR Version 2. Monitor the RTR and
application processes for increased page fault rates, and increase process memory
quotas if required.
Performance Tips 7–1