2. USAGE GUIDELINES › 2.2 Data Source Background › 2.2.1 Transaction vs. Task vs. Interaction

2.2.1 Transaction vs. Task vs. Interaction

The unit of work performed under CICS, or any online system,
is dependent on the perspective of the person defining the
unit.  The following definitions apply for the CA MICS CICS
Analyzer:

   o  Interaction

      An interaction is one piece of a conversation between
      the terminal user and CICS.  An interaction begins when
      the user enters a request to CICS from the terminal.
      It ends when CICS displays the results of the user's
      request on the terminal.

   o  Transaction

      The transaction is a unit of work that consists of
      zero, one, or more interactions between the user and
      CICS.  Typically, a transaction results in a single
      reply being sent back to the user's terminal; it ends
      after the reply is issued and does not require a second
      input from the terminal.  Other times, a transaction
      may involve several interactions between the terminal
      user and CICS, in which case the transaction is known
      as a "conversational" transaction.  In some cases, a
      transaction is started without input from a terminal.
      Such transactions consist of zero interactions.

   o  Task

      A task is the CICS internal representation of a
      transaction.  It begins when CICS associates a
      transaction with a control block called the Task
      Control Area (TCA) and ends when the TCA is no longer
      in existence.  Depending on the types of processing, a
      transaction may require the initiation of one or more
      tasks.

CMF and ASG-TMON provide data at the transaction level.
However, there are some differences between CMF and the
others in recording data for conversational tasks.

For ASG-TMON, a conversational task automatically generates
multiple transaction records.  Thus, both conversational and
nonconversational tasks are reported on the same basis; one
record is written for each interaction.

For CMF, a conversational task can generate one or more
performance class transaction records depending upon the
parameter that you specify.  To get a separate CMF record for
each interaction of the conversational task, you must specify
the SIT parameter MNCONV=YES for CICS TS 1.2 and higher
releases, or CONV=YES in the DFHMCT macro in pre-CICS TS
releases.  The default value is NO for all CICS releases,
which means CMF produces one transaction record for the
entire conversational task.