Monitoring and configuring FCM for optimal performance

FCM is an abbreviation for Fast Communication Manager. It is activated if you are using intra-partition parallelism or multipartitioned databases. The Fast Communication Manager as structure is composed by FCM buffers and FCM channels. It has a very important role in ensuring the communication between database partitions and between query slaves (subagents) and the coordinator agent when using intra-partition or inter-partition query parallelism.

Getting ready

In this recipe, we'll try to figure out the main components of FCM functionality. We'll cover some methods used for determining the performance of FCM in our NAV partitioned database created in Chapter 2, Administration and Configuration of the DB2 Non-partitioned Database.

How to do it...

Let's activate FCM usage for the NAV non-partitioned database:

1. To see the FCM buffers currently allocated for the db2inst1 instance, issue the following query:

   db2 "SELECT member, buff_free, buff_free_bottom...