Hitachi HPAV for z/OS user guide (HITA737-96006, June 2008)
Table Of Contents
- Contents
- Compatible PAV Function for the XP1024/XP128/XP12000/XP10000
- Overview of Compatible PAV Operations
- Preparing for Compatible PAV Operations
- Performing Compatible PAV Operations
- Monitoring Compatible PAV Activities
- Additional MVS Commands
- GTF I/O Tracing
- Figure 13 Sample Output of Display Command - Compatible PAV Base Device with 5 Aliases
- Figure 14 Sample Output of Display Command - Compatible Hyper PAV with 16 Aliases
- Figure 15 DEVSERV DISPLAY PATHS Command
- Figure 16 Sample DEVSERV QPAV Command (Compatible PAV)
- Figure 17 Sample DEVSERV QPAV Command (Compatible Hyper PAV)
- Figure 18 Sample Output of DEVSERV QPAV,SSID=xxxx Command (Compatible PAV)
- Figure 19 Sample Output of DEVSERV QPAV,SSID=xxxx Command (Compatible Hyper PAV)
- Figure 20 Sample Output of DS QP,xxxx,VOLUME Command (Compatible PAV)
- Figure 21 Sample Output of DS QP,xxxx,VOLUME Command (Compatible Hyper PAV)
- Figure 22 Sample Output of D IOS,HYPERPAV Command
- Using HCD to Define and View XP1024/XP128/XP12000/XP10000 LCUs and Compatible PAV Devices
- Using HCD to Define an XP1024/XP12000/XP10000 LCU and the Base and Alias Devices
- Figure 23 Basic HCD Panel
- Figure 24 Define, Modify, Or View Configuration Data
- Figure 25 Add Control Unit Panel
- Figure 26 Selecting the Operating System
- Figure 27 Select, Change Option
- Figure 28 Control Unit Chpid, CUADD, and Device Address Range Addressing
- Figure 29 Define, Modify, Or View Configuration Data
- Figure 30 I/O Device List
- Figure 31 Add Device
- Figure 32 Device / Processor Definition Panel - Selecting the Processor ID
- Figure 33 Define Device / Processor Panel
- Figure 34 Define Device to OS Configuration Window - Selecting the OS Configuration
- Figure 35 Select / Disconnect Option
- Figure 36 Define Device Parameters / Features
- Displaying Compatible PAV Device Parameters
- Using HCD to Define an XP1024/XP12000/XP10000 LCU and the Base and Alias Devices
- Checking the WLM PAV Settings
- Settings about Compatible Hyper PAV
- Index
18 Overview of Compatible PAV Operations
NOTE: If you will be using static Compatible PAV, determine on which devices I/O requests are likely to
converge, and then assign more aliases to those base devices. If not, Compatible PAV might not be able to
provide much improvement in host access to data in the XP1024/XP128/XP12000/XP10000.
Figure 3 Static Compatible PAV
Dynamic Compatible PAV
When dynamic Compatible PAV is used, the number of aliases for a base device may change as the
number of I/O requests to the device changes. If I/O requests converge on several base devices, the
number of aliases for these devices may increase, while the number of aliases for other base devices may
decrease. Dynamic Compatible PAV operations can balance workloads on base devices and optimize the
speed for accessing data in the XP1024/XP128/XP12000/XP10000.
The following figure shows an example of dynamic Compatible PAV operations. Each of the three base
devices (x10, x11, and x12) was originally assigned two aliases. In this example, as I/O requests converge
on base device x10 (shown by the large arrow), the number of aliases for device x10 increases to four,
while the number of aliases for base device x11 and x12 decreases to one.