TRANSFER Installation and Management Guide

Controlling Priorities
Managing a TRANSFER System
068837, Update 1 to 013198 Tandem Computers Incorporated 11–3
Controlling Priorities You can make your TRANSFER system more efficient by controlling the priorities of
the jobs it performs. You can manipulate job priority by controlling the parameters for
package delivery, by restricting the time when work with low priority is processed,
and by using cleanup TAREQs for housekeeping tasks.
Setting Package Delivery Parameters
When a package is sent, several parameters are involved in the actual delivery. The
default values for these parameters are in the TRANSFER correspondent profile for the
sender of the package. These values can be overridden when a package is posted for
delivery. Package delivery parameters specify delivery timeframes, expiration times,
and priorities.
The delivery parameters for an individual package must be within the limits set for
package delivery by the TRANSFER system control parameters. These limits define
the maximum package lifespan, the minimum delivery window, and the minimum
expiration window for packages posted at your node.
When you are establishing rules for package delivery parameters, consider the
following:
A wide timeframe for the delivery window, which is the time period from earliest
possible delivery to latest possible delivery, ensures that more packages are
successfully delivered.
Note Packages are not deleted from the system until after the close of the delivery window, even if they are not
saved in a folder. Remember that your database must be large enough to accommodate every package
that falls within the window.
If expiration of a package is scheduled, a wide timeframe for the minimum
expiration window, which is the minimum time period from latest delivery of a
package to expiration of the package, provides greater probability that the
recipient will examine the package before the expiration time is reached.
When TRANSFER is determining the order in which packages are delivered,
priority supersedes submission time; therefore, high-priority packages could keep
other packages from being delivered on time.
TRANSFER sends additional packages to correspondents when submitted
packages are canceled, expire, or cannot be delivered. These packages sent by
TRANSFER contribute to package traffic as well as to the size of the files
containing the packages queued for delivery.
In summary, too narrow delivery windows, too early expiration of packages, and too
many high-priority packages can affect system performance.