2. PERFORMANCE REPORTING ANALYSIS › 2.4 I/O Configuration Analysis › 2.4.5 DASD Skew Analysis Inquiry › 2.4.5.4 Component Operation › 2.4.5.4.3 Global Data Selection Panel
2.4.5.4.3 Global Data Selection Panel
If you enter Y (Yes) in the Specify global data selection
exit field, the Global Data Selection Panel, which is shown
in Figure 2-112, is displayed. This panel allows you to enter
SAS statements that will perform special data selection
functions in addition to the normal DATE/HOUR/ZONE option on
the main inquiry panel.
Special considerations come into play for 3380D/E, 3380J/K
and 3390 devices. These devices may use either the Device
Level Select (DLS) architecture or Device Level Select
Enhanced (DLSE). DLS allows any two devices on a string to
be active at any time and DLSE, which requires a 3990-2 or
3990-3 control unit, allows any four devices to be active.
Only 3390J/K and 3390 devices can take advantage of DLSE.
Both DLS and DLSE eliminate an internal path structure that
can be analyzed via the substring function. Hence, the
3380D/E/J/K devices must be represented to the DASD Skew
Analysis routine as being different than the earlier 3380
devices. Prior to RMF version 4.2, the data only identifies
these devices as 3380, and you must tell the inquiry that you
are using 3380D/E or 3380J/K devices. Furthermore, for
3380J/K attached to 3990-2 or 3390-3 control units operating
in DLSE mode, the DASD skew report cannot determine this
situation prior to RMF version 4.2. Consequently, it is
necessary to tell the inquiry that 3990 control units are
being utilized so that the inquiry reports on an assumption
of DLSE architecture.
The recommended method of doing this in a "pre-RMF 4.2"
environment is to specifically identify, via the global data
selection exit, each 3380D/E or 3380J/K device address. For
instance, if you have configured 3380Js on device addresses
480 through 48F and 580 through 58F, and they are attached to
a 3990 control unit, you would create code like that shown in
Figure 2-112.
/-------------------------------- SAS Statements -------------------------------\
| Command ===> Scroll ===> CSR |
| |
| Inquiry Step: IOA DASD Skew Analysis |
| |
| Line Cmds: I Insert D Delete R Repeat M Move C Copy |
| |
| Cmd SAS Statements for: Specifying global data selection |
| - ------------------------------------------------------------------------ |
| _ - %MACRO SELECT; |
| _ - IF DEVADDR = :'48' OR DEVADDR =:'58' THEN DO; |
| _ - DEVTYPE = '3380J';___________________________________________________ |
| _ - CTLUNAME = '3990-2';_________________________________________________ |
| _ - END;____________________________________________________________________ |
| _ ________________________________________________________________________ |
| _ ________________________________________________________________________ |
| _ ________________________________________________________________________ |
| _ ________________________________________________________________________ |
| _ ________________________________________________________________________ |
| _ ________________________________________________________________________ |
| _ - %MEND SELECT; |
| ****************************** BOTTOM OF DATA ******************************** |
| |
\-------------------------------------------------------------------------------/
Figure 2-112. SAS IOA DASD Skew Analysis Report Global Data Selector Panel
