TRANSFER Installation and Management Guide

Using Cleanup TAREQs
Managing a TRANSFER System
11–4 068837, Update 1 to 013198 Tandem Computers Incorporated
Restricting the Priority Window
You can restrict the processing of work with priorities lower than a specified value to
within a specific window of time. For example, you can allow work with a priority of
50 or less to be handled only between 8 p.m. and 5 a.m., freeing the system to
concentrate on higher-priority work during the other hours.
You can implement the restriction window by specifying three parameters to the
TSCHED server, as explained in Section 7, “Customizing a TRANSFER System,”or you
can configure this feature through the DEFINETR file, as explained in Section 5,
“Defining a TRANSFER System.”
With the priority restriction window you can postpone processing of housekeeping
work until after office hours. Because housekeeping work has a priority of 0 in the
READY file and after-hours usually means between 6 p.m. and 7 a.m., you might set
the parameters as follows:
RESTRICTPRIORITYVALUE = 0
RESTRICTPRIORITYBEGIN = 18
RESTRICTPRIORITYEND = 7
If you have, for instance, created a program for mail classes, where you want lower-
priority mail to go out only during slow hours, you can set the
RESTRICTPRIORITYVALUE to 50 so that these low-priority packages get processed
only during the restricted window.
Lower-priority work is not done except during the specified timeframe even if there is
no other work to be done.
Using Cleanup TAREQs In TRANSFER, all asynchronous work is processed by a set of PATHWAY pseudo-
terminals called TAREQs, which are configured when you install or redefine your
system. Each TAREQ requests work to do from the scheduler process, TSCHED.
TSCHED searches the READY file and allocates work according to its priority and the
time that it was requested. If, for example, the READY file has work with priorities of
100, 50, and 0, the priority 100 jobs get processed first.
On busy nodes, where many packages are constantly submitted, housekeeping work
such as end sessions, unsave items, or delete items do not get done and, therefore,
build up in the READY file because they are at priority 0.
You can configure special cleanup TAREQ pseudo-terminals that are given only
priority 0 work to do. In this way, even if there are hundreds of high-priority entries
in the READY file, housekeeping work gets done. The regular TAREQs also continue
to process priority 0 work if there is no higher-priority work to be done.
Cleanup TAREQs are necessary only if the node is very busy and you find priority 0
work stacking up in the READY file. You can check the status of the READY file using
TMANAGER.