Work process types in SAP AS

Types of Work process in SAP AS are:

The dispatcher distributes the request to the work processes.
1. DIALOG Work process
2. BACKGROUND or BATCH Work process
3. UPDATE Work process
4. ENQUEUE Work process
5. SPOOL Work process

Dialog work processes full fill all requests for the execution of dialog steps triggered by an active user. Every dispatcher requires at least two dialog work process.We can alter the number of Dialog work processes using the following parameter rdisp/wp_no_dia.
Dialog work process will take 75 - 150 MB of Physical Memory,we can increase dialog number up to 100 depends on RAM size.

Background work processes executes programs that run long time and recurring without interacting with the user. You need at least two background work processes for each SAP system.We can alter the number of Background work processes using the following parameter rdisp/wp_no_btc.

Spool work processes pass sequential data flow on to printers. At least one spool work process is required for each SAP system. It is possible to configure more than one spool work process for each dispatcher. Wecan alter the number of Spool work processes using the following parameter rdisp/wp_no_spo.

Update work processes executes update requests. Similarly to spool work processes, you need at least one update work process per SAP system.

We can alter the number of Update work processes using the following parameter rdisp/wp_no_vb.

There are two processes that are related to the update process

UPD - update process for making U1 (time-critical) database changes
UP2 - update process for executing U2 (not time-critical) database changes.

The Enqueue work process administers the lock table in the shared memory. The lock table contains the logical database locks of the ABAP runtime environment of the SAP system. Only one enqueue work process is needed for each system.We can alter the number of Update work processes using the following parameter rdisp/wp_no_enq.