V-VOL cache initialization

Provisioning Guide for VSP One Block

Version
10.2.x
Audience
anonymous
Part Number
MK-23VSP1B012-00

If the total cache initialization capacity for V-VOLs created at once is large, the processing might time out. To calculate the cache initialization capacity for V-VOLs, use the following mathematical expression:

cache-initialization-capacity = ceil (defined-capacity [TB] ÷ 2.99 [TB]) × 2.99 [TB]

where

The value enclosed in ceil ( ) must be rounded up to the nearest whole number.

The total cache initialization capacity for V-VOLs created at once can be obtained by calculating the cache initialization capacity for each V-VOL and then adding them up.

If the number of V-VOLs to be created at once exceeds 256, 256 V-VOLs are created per creation on the storage system.

To prevent this processing from timing out, the total cache initialization capacity for up to 256 V-VOLs to be created should be at most 8 PB. If 8 PB is exceeded, limit the defined capacity for V-VOLs to be created at once to less than 8 PB, verify that the V-VOL creation processing is complete, and then create the next V-VOLs.

Example:

When a V-VOL is 29.9 TB, the total cache initialization capacity is less than 8 PB, and therefore the processing does not time out.

ceil (29.9 [TB] ÷ 2.99 [TB]) × 2.99 [TB] = 29.9 [TB]

29.9 [TB] × 256 = 7,654.4 [TB]

The value enclosed in ceil ( ) must be rounded up to the nearest whole number.

Example:

When a V-VOL is 29.91 TB, if more than 249 V-VOLs are created, the processing might time out.

ceil (29.91 [TB] ÷ 2.99 [TB]) × 2.99 [TB] = 32.89 [TB]

floor (8,192 [TB] ÷ 32.89 [TB]) = 249

The value enclosed in floor ( ) must be rounded down to the nearest whole number.