How to decrease the provisioned size of a volume in Pure Flash Array storage using CLI

The pure Flash array uses Purevol setattr command to increase the provisioned storage space for volume. Similarly, Flash Array also gives an option to reduce the allocated storage space for a volume. The purevol truncate command reduces the provisioned volume size. As per pure CLI, the volume size cannot be reduced below 1 megabyte and cannot be increased greater than 4 petabytes. 

When a volume is truncated, the Pure flash array automatically takes a volume snapshot. This snapshot has 24 hours expiration window and can be used to retrieve the previous state of the volume before size reduction. We must be extremely cautious while performing the volume truncate command as the chances of volume corruption are high if data resides in the truncated sectors.

syntax: purevol truncate --size SIZE VOL

  --size SIZE  new virtual size

pureuser@flasharray1> purevol create --size 15G PRODVOL01
Name       Size  Source  Created                  Serial
PRODVOL01  15G   -       2021-12-16 07:49:44 PST  66C228E8DB224F9D000113FB
pureuser@flasharray1> purevol list PRODVOL01
Name       Size  Source  Created                  Serial
PRODVOL01  15G   -       2021-12-16 07:49:44 PST  66C228E8DB224F9D000113FB

following command will reduce the provisioned size of pure volume 

pureuser@flasharray1> purevol truncate --size 10G PRODVOL01
Name       Size
PRODVOL01  10G