Chapter 1. What Is CMFMON? 3
• Refresh the display continuously in auto-update mode.
• Write CMFMON screen information directly to SYSOUT.
Because CMFMON’s interface is an ISPF application, you have full use of all of ISPF’s
powerful commands. For example, you might want to use the ISPF PRINT command to
capture screens or the SPLIT and SWAP commands to run CMFMON in a secondary ISPF
session, retaining your primary session for other purposes.
CMFMON
and
CMF
MONITOR
Online
If you are familiar with CMF MONITOR Online, think of CMFMON as an alternative way to
access the same kind of data. However, while you would probably choose CMF MONITOR
Online if you required certain features provided by MainView architecture, such as multi-
system support, access to historical data, and so on, you might choose CMFMON’s online
facility if you needed quick or temporary access to realtime system data. And, while CMF
MONITOR Online data is averaged over an interval or over the life of a job, CMFMON data is
updated every time you press Enter, to keep you informed of exactly what is changing and
where.
CMFMON
and
RMFMON
If you are familiar with IBM’s RMF MONITOR II (RMFMON), you have probably noticed
that CMFMON provides all the data that RMFMON provides. In addition, CMFMON offers a
special unique screen: the ASL screen. By combining key data elements from the ARD and
ASD screens, ASL provides a comprehensive overview of the jobs currently active on your
system, enabling you to gauge application performance in a single glance. CMFMON also
provides the XDSA (XDS buffer activity) screen, which summarizes the XDS buffer contents
by SMF record type and subtype.
To find out how to use CMFMON’s online facility, see Chapter 2, “Using CMFMON’s Online
Facility” on page 5. If you just want an overview of the commands available in CMFMON’s
online facility, take a few moments to browse Appendix D, “Quick Reference for CMFMON’s
Online Facility” on page 101.
Understanding CMFMON’s Write Facility
You can think of CMFMON’s write facility as an extension to the CMF Extractor. A
CMFMON recording session running independently of the CMF Extractor can collect
information on several areas of system activity, including address spaces, channels, system
paging, and enqueue contention. A CMFMON recording session running simultaneously with
an Extractor session can produce records that overlap some areas of Extractor session
measurements, including transactions, I/O devices, I/O queuing, and page/swap data sets.
Whereas the Extractor writes SMF record types 70 through 78, CMFMON’s write facility
writes SMF type 79 records—and all its subtypes—to either an SMF or a sequential data set.
CMFMON also provides the means to more specifically identify the individual resources for
which you want to collect performance measurements. Using CMFMON control statements,
you specify the type of data you want to collect for given resources, at what interval, and for
how long.
Chapter 3, “Using CMFMON’s Write Facility” on page 37, explains how to code the control
statements.
