SirFile
(A print-quality
reproduction of this brochure is available in
pdf format.)
Managing the physical storage utilization of Model 204
files is a critical, yet often overlooked aspect of Model 204
performance and reliability. The costs of not performing timely
physical file management range from poor utilization of DASD,
to the steady erosion of database performance to the abrupt failure
of applications. A table full condition requires that the offending
file be removed from the on-line and reorganized. To do so requires
that the person responsible identify all users using the file,
notify and bump them, dump and restore the file with more space
allocated. This can mean that critical applications are unavailable
for hours.
Effective file management is a widespread concern
in Model 204 shops because of staffing shortages and the
lack of adequate monitoring tools. This is especially acute for
shops having dynamic files with a large number of updates. Those
responsible simply don't have the time to keep all the files in
the system properly sized. Constant monitoring is required because
Model 204 provides no reliable way to track file growth patterns
and predict, in advance, exactly when a file will need reorganization.
SirFile Main Screen, below, is showing
monitored files.
Automated File Monitoring
SirFile is a totally automated file monitoring utility
from Sirius Software. SirFile automates the monitoring and tracking
of storage utilization in Model 204 files. SirFile requires
no operator intervention. It compiles file and table size information
automatically. SirFile runs as a background task monitoring and
collecting historical file information and notifies the designated
personnel when critical file conditions will occur.
SirFile maintains a database of historical file information
that is automatically updated at user-specified intervals. An
online query system provides a menu of Model 204 files with
problem files highlighted before they fill up. Detail screens
provide additional information about the particular problem file.
This advance notice allows operations to schedule file expansions
or reorganizations before end users experience a disruption. Using
SirFile produces a substantial time savings for the System Manager
or DBA.
Selecting "
SIRXREFD"
file on
Main Screen and entering PF10 shows the detail screen below.
Historical Tracking
SirFile tracks the current status and, based upon
the historical usage, determines the growth rate of key file statistics.
These include the percentage full statistic for each table, the
number of retries in the hashed tables, and the number of extension,
overflow, and spill records. The user can customize how SirFile
collects the file data by specifying the number of samples to
store for each file, the number of days between stored samples
and the amount of advance warning SirFile should provide when
a file is approaching a threshold.
SirFile predicts file-full conditions. After the
first time SirFile is invoked, subsequent samples are used to
determine the rate of growth for each file statistic. If the predicted
table-full date falls within a user-specified window, a prediction
message is posted in the SirFile database, and the file is highlighted
on the SirFile screens.
Besides warnings and predictions, SirFile provides
detail views of file statistics and activity, and a view of the
table-full status of each file open in the region.
Easy Setup and Operation
Setup is fast and simple. The first SirFile user
either accepts a series of default values or defines a screen
of threshold values above which any file is considered to be inefficiently
structured or in danger of filling. SirFile refreshes its internal
database, automatically comparing each file in the region to the
defined threshold for that file.
Once an initial set of observations is collected,
the user may customize SirFile by adding other files to the system
manually, or by changing special file-specific thresholds. For
instance, the default threshold may be set to issues a warning
if Table D becomes more than 85% full. A particular file may be
95% full, but not expected to grow. A Table D threshold to 96%
can be defined for this file. This eliminates unnecessary table-full
warnings, but causes SirFile to notify a designated user if any
Table D growth occurs in the file.
Threshold settings for the "
SIRXREFD"
file.
The SirFile refresh can be run either in online or
batch mode. Running the refresh in batch allows the resource-intensive
portion of SirFile to be offloaded and scheduled. Running the
refresh in an online provides up-to-the-minute file status. The
refresh process can be run as often as required, in batch or online.
SirFile will regulate itself, keeping only as much data as is
needed to predict file growth and to keep the user informed about
critical file statuses.
The refresh process can also be run as a background
task in an online. The user specifies a sleep interval and a list
of users to receive warnings and predictions. SirFile can then
be invoked either in the USER0 job stream or in an IODEV3 session,
so the background task runs automatically each time the online
is brought up. Once configured, this background task invisibly
handles all file monitoring tasks.
Summary
SirFile is an automated file monitoring and management
tool. Its use will greatly reduce the amount of time and effort
expended in managing Model 204 files. Using the information
and warnings provided by SirFile will allow the systems managers
and operations staff to increase the efficiency of the Model 204
applications, reduce the DASD requirements for the systems, and
eliminate system down time due to unplanned file maintenance.
SirFile runs under any supported version of Model 204.
It is available under MVS, VM/CMS and VSE operating systems.
