Advanced JVM Options for SIP Requests

You can change the DNS cache size and the number of SIP timer queues, which may improve the performance of SIP request processing.

The DNS cache ensures that consecutive lookup requests of a certain TEL URI initiated by an application do not trigger more than one external DNS/ENUM request. To configure the DNS cache, set the maximum number of cache entries using the asadmin create-jvm-options command. For example:

asadmin create-jvm-options --user adminuser -Ddns.cache.size=10000

The default value is 50000. A value of -1 is interpreted as setting no limit on the number of entries.

The number of SIP timer queues is configurable. When the SIP request load is high, adding more SIP timer queues may improve performance. To set the number of SIP timer queues, use the asadmin create-jvm-options command. For example:

asadmin create-jvm-options --user adminuser -Dorg.jvnet.glassfish.comms.sip.timer.queues=5

The default value is 1. Allowed values are integers between 1 and 10 inclusive.