To deliver optimal performance for Lotus Connections, it is important to set a few WebSphere Application Server parameters for our Enterprise level deployment. There are three main focus areas:
- Operating system changes required
- JVM size for each server
- Connection pool size for each data source
- Prepared statement cache size for each connection pool
Operating system changes required
As this is a 32-bit OS, Physical Address Extension (PAE) must be enabled on those machines requiring more than 4 GB RAM. Consult the Red Hat documentation for instructions.
It is a requirement that all of the machines in the network deployment have their system clocks synchronized. To do so, enable each machine to synchronize with an external time server.
JVM size for each server
For a large scale enterprise deployment, it is recommended to increase the JVM heap size from its default value for each server to achieve optimal performance. Increase the heap size to the following values for each server on each node:
When increasing the heap size, it is a good idea to monitor overall memory consumption to ensure that your system can provide the necessary memory allocations without excessive paging. To facilitate the increased heap size in this example, the node machines have 16 GB of RAM, which is more than enough memory.
To modify the heap size, do the following:
1. From the WebSphere Application Server administrative console select
Servers > Application Servers.
A complete list of all the servers on each node is displayed. Select the server that you want to modify. To do so,click the name field for that server (for example, activitiesServer).
2. From the next window under the Server Infrastructure settings, select
Java and Process Management > Process Definition > Java Virtual Machine.
3. Set the maximum heap size.
4. Click
OK and save changes.
5. Repeat this process for each server on which you want to increase the heap size.
Connection pool size for each data source
Tuning each connection pool is an important step to ensure optimal response times. An improperly tuned environment might mean unnecessary time spent waiting for a free connection. Setting the pool sizes large enough eliminates this risk, but it is also important to respect the overall system resources on the application server by not setting this value higher than necessary for the expected peak workloads. Increasing the default value of 10 connections to 50 is a safe assumption for any size of deployment and should not have a negative impact on overall system resources.
Tuning to higher values, such actions, might be needed to support maximum load for some of the components in a large deployment. However, as you tune these values higher, keep an eye on overall memory consumption to ensure that your system is able to provide the necessary memory allocations without excessive paging.
To set the connection pool for each data source, follow these steps:
1. From the WebSphere Application Server administrative console, select
Resources > JDBC > Data Sources. A list of data sources for each of the components is displayed. For each component, there is a data source for each node and the cluster. In this example, the data source for Activities on node 1 is selected for modification.
2. Click the
activities link and select
Connection Pool properties from the top right of the next page.
3. Set the maximum number of connections to 50 as shown:
4. Click
OK and save these changes.
5. Repeat this process for the other data sources as required.
Prepared statement cache size for each connection pool
It is recommended to increase the default prepared statement cache size from 10 to a value closer to 100. To modify the statement cache size, do the following:
1. Open the data source similar to step 2 above.
2. Select
WebSphere Application Server data source properties from the top right of the page.
3. This time, you are presented with the following window where you can modify the cache size:
4. Click
OK and save these changes.
5. Repeat this process for all of the data sources as required.
There are many possible tweaks and modifications that can be made on WebSphere Application Server to tune the configuration for optimal performance depending on your requirements. For further information, consult the Lotus Connections 2.5 tuning articles available on the Lotus Connections Wiki at:
http://www-10.lotus.com/ldd/lcwiki.nsf/
Go to the next topic:
S2: Scenario environment
S2: Prerequisites
S2: Configuration diagrams
S2: Machine details
S2: Installing Lotus Connections in an Enterprise level deployment
S2: Starting Lotus Connections
S2: Configuring an administrative user for Blogs
S2: Integrating Lotus Connections with Lotus Quickr for WebSphere Portal
S2: Enabling Sametime awareness on Lotus Connections
S2: Troubleshooting
Table of Contents:
Lotus Connections 2.5 Enterprise level deployment scenario