Topic
  • 4 replies
  • Latest Post - ‏2012-11-21T05:04:02Z by SriramIyer-StorageSSR
SriramIyer-StorageSSR
10 Posts

Pinned topic Disable Easy Tiering in V7000

‏2012-10-30T11:51:12Z |
Hi all

One of my clients has the following scenario :-

Pool 'A' has easy tiering enabled. (SSD mdisk is present and easy tier is in auto mode)

Now there are 3 volumes 'x', 'y' and 'z' in above pool and obviously all have easy tiering enabled.

Suppose, volume 'x' has 100GB data on SSD and remaining 500GB on SAS and customer feels this volume no longer needs high iops of SSD and has decided to disable easy tiering on this volume using chvdisk -easytier off x

Now in the next easy tier algorithm cycle will 100GB data present in SSDs migrate back to SAS automatically since easy tiering is no longer active on this volume or will it remain in SSD till some other hotter data displaces it ?

Please help.

Thanks
Sriram Iyer
Updated on 2012-11-21T05:04:02Z at 2012-11-21T05:04:02Z by SriramIyer-StorageSSR
  • karl.h
    karl.h
    64 Posts

    Re: Disable Easy Tiering in V7000

    ‏2012-11-18T23:00:24Z  
    The data will not be migrated to the SAS drives. As soon as you disable EasyTier on the volume there will be no more automatic data placement. So if you want to remove the data from the SSDs when EasyTier is disabled on the volume you need to do this manually.
  • SriramIyer-StorageSSR
    10 Posts

    Re: Disable Easy Tiering in V7000

    ‏2012-11-19T05:05:04Z  
    • karl.h
    • ‏2012-11-18T23:00:24Z
    The data will not be migrated to the SAS drives. As soon as you disable EasyTier on the volume there will be no more automatic data placement. So if you want to remove the data from the SSDs when EasyTier is disabled on the volume you need to do this manually.
    Hi Karl

    After disabling easy tier for this volume is there any way by which i can migrate the extents of only this volume from SSD to SAS ??
  • karl.h
    karl.h
    64 Posts

    Re: Disable Easy Tiering in V7000

    ‏2012-11-21T00:30:04Z  
    Hi Karl

    After disabling easy tier for this volume is there any way by which i can migrate the extents of only this volume from SSD to SAS ??
    Hi,
    yes depending on your setup there are different options. If you have more than 1 pool you can migrate the volume to another pool so all the extends will be migrated off the SSDs. If you only have 1 pool you need to use the CLI to migrate the extends off your SSDs. You need to use the command "svctask migrateexts".
    Here a link to InfoCenter for more details on the command.
    http://pic.dhe.ibm.com/infocenter/storwize/ic/index.jsp?topic=%2Fcom.ibm.storwize.v7000.doc%2Fsvc_migratingextentscli_2ns0s.html

    When using the command try to distribute the extends evenly on your SAS mdisks (Arrays).

    Hope this makes sense.
  • SriramIyer-StorageSSR
    10 Posts

    Re: Disable Easy Tiering in V7000

    ‏2012-11-21T05:04:02Z  
    • karl.h
    • ‏2012-11-21T00:30:04Z
    Hi,
    yes depending on your setup there are different options. If you have more than 1 pool you can migrate the volume to another pool so all the extends will be migrated off the SSDs. If you only have 1 pool you need to use the CLI to migrate the extends off your SSDs. You need to use the command "svctask migrateexts".
    Here a link to InfoCenter for more details on the command.
    http://pic.dhe.ibm.com/infocenter/storwize/ic/index.jsp?topic=%2Fcom.ibm.storwize.v7000.doc%2Fsvc_migratingextentscli_2ns0s.html

    When using the command try to distribute the extends evenly on your SAS mdisks (Arrays).

    Hope this makes sense.
    Thanks Karl.. Really helpful insight