Estimating The Number Of Concurrent Manual Migration Plans; Fixed Parity Groups - HP XP P9500 User Manual

installed, you may use 104,768 or 209,600 differential tables. You may also use 146,688,
or 209,600 differential tables.
To install additional shared memory for differential tables, call HP Technical Support.
The amount of shared memory available for pair tables. You can install additional shared
memory for pair tables. You may use 16,384 pair tables if additional shared memory for pair
tables is installed.
To install additional shared memory for pair tables, call HP Technical Support.
The emulation type and capacity of each volume to be migrated.
The number of differential tables and pair tables needed to migrate one volume differs based
on the emulation type and size of the volume. For the number of differential tables and pair
tables needed for migrating a mainframe volume, see
differential tables for a mainframe volume" (page
needed for migrating an open-system volume, see
differential tables for an open-system volume" (page

Estimating the number of concurrent manual migration plans

The following conditional expression can be used to estimate the maximum number of migration
plans that can be executed concurrently:
Σ(α) ≤ (β) and Σ(γ) ≤ (δ)
The variables are explained below:
Σ (α): total number of differential tables needed for migrating all volumes.
(β): total number of differential tables available in the storage system.
Σ (γ): total number of pair tables needed for migrating all volumes.
(δ): total number of pair tables available in the storage system.
As calculated in
differential tables required for each migration plan for an OPEN-3 volume is 3, and the number
of required pair tables for each migration plan is 1. If you want to create 20 migration plans of
OPEN-3 volumes, 60 differential and 20 pair tables are required. These numbers are plugged into
the original equation:
[ (3 x 20) = 60 ] ≤ 26,176 and [ (1 x 20) = 20 ] ≤ 8,192
Because this expression is true, you can create all 20 migration plans for the OPEN-3 volumes.
In the preceding calculation, it is assumed that only Auto LUN is running. However, as mentioned
earlier, differential tables are resources that are also shared by Snapshot, Business Copy, Business
Copy for Mainframe, and Compatible FlashCopy. The total number of pair tables used by Business
Copy, Business Copy for Mainframe, Compatible FlashCopy and Auto LUN should be within the
value of (β) and (δ). For details on how to calculate the number of differential tables and pair
tables used by the programs other than Auto LUN, see the manuals of the corresponding products.

Fixed parity groups

If the Auto Migration function is enabled, some volumes and parity groups might experience
degraded I/O speeds. For example, if volume 00:00:01 is migrated from the parity group Grp1- 1
of class A to the parity group Grp-2- 1 of class B, volume 00:00:01 is migrated to a lower-speed
hard disk drive and might suffer a delay in I/O speed. If you specify Grp1- 1 as a fixed parity
group, volumes in Grp1- 1 will not be migrated to any other parity group, and no volumes will be
migrated to Grp1- 1 . This action protects a parity group from degraded I/O speeds.
NOTE: In a manual migration plan, you can specify a volume in a fixed parity group as a target
or a source volume.
20 Auto LUN planning
"Differential tables calculation for an OPEN-V volume" (page
"Calculating the required amount of
17). For the number of differential tables
"Calculating the required amount of
18).
18), the number of