Set Thin Provisioning

Overview

This function enables or disables the use of the Thin Provisioning function and sets the maximum pool capacity that can be created in the storage system. The maximum pool capacity is the maximum total capacity for TPPs and FTRPs that can be created in the storage system. The chunk size is determined by the specified maximum pool capacity.

For the maximum pool capacity and determined chunk size for each model, refer to "The Maximum Number of Pools, Maximum Pool Capacity, and Determined Chunk Size for Each Model".

Caution

  • Note that the Thin Provisioning function is not provided for the ETERNUS DX60 S5/DX100 S5/DX200 S5 1CM model. In addition, the "Thin Provisioning" navigation is not displayed for these models.

  • If the following conditions are all satisfied, the Thin Provisioning function can be enabled.
  • The Thin Provisioning function cannot be disabled in the following conditions.

    • TPPs exist in the storage system

    • "TPV balancing" is selected for the Thin Provisioning allocation mode

    • The Automated Storage Tiering feature is enabled (*1)

      *1  :  Enabling or disabling the Automated Storage Tiering feature is performed by using ETERNUS SF Storage Cruiser.

  • Cache memory is not only used for the Thin Provisioning function (*1), but also used for copy tables, REC Buffers, the Storage Cluster function (*2), the Non-disruptive Storage Migration function, and the Extreme Cache function. Note that an REC Buffer with the maximum capacity for each model cannot always be created depending on the following conditions.

    • Memory capacity in the storage system

    • Copy table size

    • REC Buffer size

    • Total TFOV capacity (*2)

    • License registration for the Non-disruptive Storage Migration function

    • Extreme Cache setting (enabled) and Extreme Cache capacity

    *1  :  The shared area in the cache memory is used for the following conditions.

    • The maximum pool capacity has been expanded to "1.5 PB" or larger

    • The total TFOV capacity (*2) has been expanded from the default capacity

      Refer to the descriptions about "Storage Cluster" in the [System] screen for the default capacity of the TFOV for each model.
    *2  :  The total TFOV capacity indicates the total capacity of the volumes that are used for the Storage Cluster function in a storage system.

  • If the Virtual Volume function is enabled, the current state (enabled or disabled) of the Thin Provisioning function cannot be changed. To check whether the Virtual Volume function is enabled or disabled, use the [System] screen. Refer to the [System (Basic Information)] function for details.

  • The FTRP capacity that can be used as Virtual Volumes (VVOLs) is different from the maximum pool capacity. Refer to "The Maximum FTRP Capacity that Can Be Used as VVOLs" for details.

  • If the maximum pool capacity is set to "4 PB" or larger, the cache mode is temporarily changed to the "Write Through" mode. The workload I/O performance of the entire storage system is lowered when the cache mode is transitioning to "Write Through Mode". Therefore, it is recommended to set a maximum pool capacity of 4 PB or larger when the work I/O is low.

Note

  • If "Disable" is selected for the Thin Provisioning function, make sure to change the Thin Provisioning allocation mode from "TPV balancing" to the default "TPP balancing" setting. Refer to the [Setup Subsystem Parameters] function for details.

Installed Drives for Each Maximum Pool Capacity

The following drives must be installed for each maximum pool capacity. There are no requirements for drive type, capacity, and speed.

Model Maximum pool capacity Number of installed drives

Installed drive location
Enclosures Slot location

ETERNUS DX60 S5

ETERNUS DX100 S5

ETERNUS DX200 S5

 - (*1) 2 CE#0 Slot#0 and Slot#1
ETERNUS DX500 S5 - (*1) 2 CE#0 Slot#0 and Slot#1
ETERNUS DX600 S5 Up to 1 PB 2 CE#0 Slot#0 and Slot#1
1.5 PB or larger 4 CE#0 Slot#0 to Slot#3

ETERNUS DX900 S5

ETERNUS DX8900 S4

 Up to 1 PB 2 CE#0 Slot#0 and Slot#1
2 PB 4 CE#0 Slot#0 to Slot#3
4 PB 8 CE#0 Slot#0 to Slot#3
DE#04 Slot#0 to Slot#3
8 PB or larger 16 CE#0 Slot#0 to Slot#7
DE#04 Slot#0 to Slot#7

ETERNUS AF150 S3

ETERNUS AF250 S3

 - (*1) 2 CE#0 Slot#0 and Slot#1
ETERNUS AF650 S3 Up to 1 PB 2 CE#0 Slot#0 and Slot#1
1.5 PB or larger 4 CE#0 Slot#0 to Slot#3
*1  : The required number of drives is fixed regardless of the maximum Thin Provisioning pool capacity.

The Maximum FTRP Capacity that Can Be Used as VVOLs

Model The maximum FTRP capacity that can be used as VVOLs

ETERNUS DX100 S5

ETERNUS DX200 S5

 256 TB

ETERNUS DX500 S5

 384 TB

ETERNUS DX600 S5

 1024 TB
ETERNUS DX900 S5 2 PB
ETERNUS DX8900 S4 2 PB

ETERNUS AF150 S3/AF250 S3

 256 TB

ETERNUS AF650 S3

 1024 TB
Caution

  • The actual available capacity that can be used as a VVOL is limited depending on whichever is smaller, the maximum FTRP capacity or the maximum pool capacity. For example, if the ETERNUS DX8900 S4 is used and the maximum pool capacity is "512 TB", the actual capacity that can be used for VVOLs is 512 TB even if the maximum FTRP capacity that can be used for VVOLs is "2 PB".

User Privileges

Availability of Executions in the Default Role

Default role Availability of executions
Monitor  
Admin
StorageAdmin  
AccountAdmin  
SecurityAdmin  
Maintainer

Refer to "User Roles and Policies" for details on the policies and roles.

Settings

Thin Provisioning Settings

Item Description Setting values

Thin Provisioning

Select whether to "Enable" or "Disable" the Thin Provisioning function.

Enable

Disable

Default

  • When the Unified Storage License is installed at the factory

    Enable

  • When the Unified Storage License is not installed at the factory

    Disable

Maximum Pool Capacity

Select the maximum pool capacity that is specified for the storage system.

The maximum pool capacity can be expanded gradually according to the used pool capacity. Because the maximum pool capacity is not fixed, memory can be more effectively used. Note that if the chunk size is changed depending on the expanded "Maximum Pool Capacity", a calculation different from the existing method is used to obtain the pool capacity that can be created.

This item is only available when "Thin Provisioning" is enabled. Note that a capacity that is smaller than the current capacity cannot be selected.

Caution

  • The actual available capacity is limited if the maximum physical capacity of the drives that can be installed is smaller than the maximum pool capacity. For example, when using an ETERNUS DX8900 S4 that is configured only with 900 GB drives, the actual capacity that can be used is approximately 3.6 PB even if the maximum pool capacity is "8.00 PB".

  • If the chunk size is changed due to the expansion of the maximum pool capacity and the maximum pool capacity has already been used up before the expansion, new pools cannot be created. For example, if the current maximum pool capacity in the ETERNUS DX8900 S4 is "8 PB" or "128 PB", the capacity that can be used to create new pools is calculated with the following formula.

    Current maximum pool capacity (Chunk size a (*1))

    [A]

    Used pool capacity (Chunk size b (*2))

    [B]

    Capacity that can be used to create new pools

    [C]

    		 Description
    8 PB (21 MB) 1 PB (21 MB) 7 PB

    The capacity that can be used to create new pools [C] is calculated with the following formula.

    [C] = [A] - [B] × (Chunk size a / Chunk size b)
    8 PB (21 MB)

    0 PB

    ↑ New pools cannot be created
    128 PB (336 MB) 1 PB (21 MB) 112 PB
    8 PB (21 MB)

    0 PB

    ↑ New pools cannot be created
    *1  :  This indicates the chunk size that is determined according to the "Maximum Pool Capacity" that is to be set with this function. Refer to "The Maximum Number of Pools, Maximum Pool Capacity, and Determined Chunk Size for Each Model" for details.
    *2  :  This indicates the chunk size that is determined by the "Maximum Pool Capacity" that had been specified in the storage system when TPPs were created. The chunk size can be checked on the [Thin Provisioning Pool] screen. Refer to the [Thin Provisioning Pool (Basic Information)] function for details.
Note

  • To reduce the maximum pool capacity, disable "Thin Provisioning". After performing this action, restart this function to enable "Thin Provisioning", and then set a new "Maximum Pool Capacity".

ETERNUS DX60 S5:

64 TB (Default)

128 TB

2 PB

ETERNUS DX100 S5:

128 TB (Default)

256 TB

4 PB

ETERNUS DX200 S5:

256 TB (Default)

384 TB

6 PB

ETERNUS DX500 S5:

384 TB (Default)

512 TB

1 PB

16 PB

ETERNUS DX600 S5:

512 TB (Default)

1 PB

1.5 PB

24 PB

ETERNUS DX900 S5 or ETERNUS DX8900 S4:

512 TB (Default)

1 PB

2 PB

4 PB

8 PB

128 PB

ETERNUS AF150 S3:

128 TB (Default)

256 TB

4 PB

ETERNUS AF250 S3:

256 TB (Default)

384 TB

6 PB

ETERNUS AF650 S3:

512 TB (Default)

1 PB

1.5 PB

24 PB

Operating Procedures

  1. Click [Set Thin Provisioning] in [Action].

  2. Select whether to enable or disable the Thin Provisioning function, specify the maximum pool capacity, and then click the [Set] button.

    → A confirmation screen appears.

    Caution

    • If the Virtual Volume function is being used and the chunk size is changed as a result of a maximum pool capacity expansion, a warning message related to the Virtual Volume function appears.

  3. Click the [OK] button.

    → The Thin Provisioning setting starts.

  4. Click the [Done] button to return to the [Settings] screen.