This section describes some recommendations for tuning your system to achieve and maintain optimal performance of distributed e-mail. Note that performance varies inevitably from case to case; therefore you should consider these values as a starting point only and experiment with the parameters listed to determine the values that best suit your configuration.
Note also that distributed e-mail is resource intensive. In addition to configuring the parameters described here, ensure that your database, network, and SMTP servers can handle the volume of traffic generated by distributed e-mail. It may be necessary to scale your hardware at each level of the targeted e-mail architecture to achieve the level of performance you require.
VM heap size: Increasing the heap size can yield a measurable performance improvement. Suggested initial value: 1024MB per server.
Instance count: Oracle recommends having one distributed e-mail server per available CPU. Oracle also suggests that the CPUs reside on a machine dedicated to distributed e-mail.
CPU binding: Leaving all processes and processors unbound may provide the highest throughput for distributed mailings. For more information, refer to the documentation for your application server.
Thread handler count on distributed e-mail server
numBatchThreadsproperty in the/atg/userprofiling/email/BatchEmailPeriodicServicecomponentThe
numBatchThreadsproperty sets the number of threads that render e-mail. Suggested initial value: 20.E-mail batch size
emailsPerBatchproperty in the/atg/userprofiling/email/TemplateEmailBatchPersistercomponentThis property specifies the number of recipient addresses that can be claimed at one time for e-mail rendering. Suggested initial value: 100.
E-mail chunking for SMTP server communication
createMessagesBatchSizeproperty in the/atg/userprofiling/email/TemplateEmailSendercomponentThe e-mail handlers send messages to the SMTP server in chunks, and the
createMessagesBatchSizeproperty specifies the size of the chunk. Oracle suggests setting this value to at least 4 (each rendered e-mail batch sent to the SMTP server contains four outbound messages).Distributed e-mail status updates
updateBatchCountsEveryNMessagesandupdateProfileStatusesEveryNMessagesproperties in the/atg/userprofiling/email/TemplateEmailSendercomponentThese properties control the frequency of status updates to the database. Suggested initial value: the size of the e-mail chunks that are sent to the SMTP server.
Scenario maximum batch size
maxBatchSizeproperty in the/atg/scenario/ScenarioManagercomponentFor very large mailings, tuning the
maxBatchSizeproperty helps control the size of the e-mail recipient list, which must be retrieved from the database. Suggested initial value: 1000 (the default setting). For more information, see Minimizing the Number of Collective Elements. Note that it is not necessary to change this setting if you are creating and sending mailing programmatically rather than through scenarios.

