Applying data access activity measurements

• US 8,380,928 B1
• Filed: 12/17/2009
• Issued: 02/19/2013
• Est. Priority Date: 12/17/2009
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Chen, Xiangping, Can, Khang, Madhukar, Manish, Harvey, David W., Throop, Dean D., Ku, Mark K.
• Primary Examiner(s): PORTKA, GARY J
• Application Number:
  US12/640,292
• Time in Patent Office: 1,160 Days
• Field of Search: None
• US Class Current: 711/117
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/3433 for load management allocation of a server based on load conditions G06F9/505; load rebalancing G06F9/5083; redistributing the load in a network by a load balancer H04L67/1029
• CPC Class Codes: G06F 11/3485 for I/O devices
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0649 Lifecycle management
• CPC Class Codes: G06F 3/0685 Hybrid storage combining heterogeneous device types, e.g. hierarchical storage, hybrid arrays

Abstract

A method is used in applying data access activity measurements. A slice relocation candidate list is generated which identifies slices to be relocated along with respective destination tier information. Slices in a pool are matched to respective matching tiers based on the slices'"'"' respective temperatures and tier preferences. Based on whether a current tier for a slice differs from the matching tier for the slice, the slice is listed in the relocation candidate list.

Claims

1. A method for use in applying data access activity measurements, the method comprising:

generating a slice relocation candidate list which identifies slices to be relocated along with respective destination tier information;

matching slices in a pool to respective matching tiers based on the slices'"'"' respective temperatures, tier preferences and the total temperature limit of the respective tiers, wherein the temperature refers to a level of access activity for the slice, the tier preference refers to an operator input and the total temperature limit of a tier is the sum of total temperature limits of all RAID groups within the tier, further wherein the total temperature limits of the RAID groups are a fraction of the maximum temperature limits of the RAID groups in order to prevent overload of the tiers; and

based on whether a current tier for a slice differs from the matching tier for the slice, listing the slice in the relocation candidate list.

2. The method of claim 1, wherein the relocation candidate list is generated by an auto-tiering policy engine.

3. The method of claim 1, wherein the relocation candidate list is based on how many slices are available for data allocation and how many slices are being used.

4. The method of claim 1, wherein the relocation candidate list is based on a maximum number of slices that can be put in the matching tier.

5. The method of claim 1, wherein the relocation candidate list is based on a preference derived from mapped LUN tier properties.

6. The method of claim 1, wherein the relocation candidate list is based on filtering out a slices with a no relocation configuration.

7. The method of claim 1, wherein the relocation candidate list is based on matching slices to tiers starting with the highest tier.

8. The method of claim 1, wherein the relocation candidate list is based on matching slices to higher tiers before lower tiers.

9. A system for use in applying data access activity measurements, the system comprising:

first logic generating a slice relocation candidate list which identifies slices to be relocated along with respective destination tier information;

second logic matching slices in a pool to respective matching tiers based on the slices'"'"' respective temperatures, tier preferences and the total temperature limit of the respective tiers, wherein the temperature refers to a level of access activity for the slice, the tier preference refers to an operator input and the total temperature limit of a tier is the sum of total temperature limits of all RAID groups within the tier, further wherein the total temperature limits of the RAID groups are a fraction of the maximum temperature limits of the RAID groups in order to prevent overload of the tiers; and

third logic listing, based on whether a current tier for a slice differs from the matching tier for the slice, the slice in the relocation candidate list.

10. The system of claim 9, wherein the relocation candidate list is generated by an auto-tiering policy engine.

11. The system of claim 9, wherein the relocation candidate list is based on how many slices are available for data allocation and how many slices are being used.

12. The system of claim 9, wherein the relocation candidate list is based on a maximum number of slices that can be put in the matching tier.

13. The system of claim 9, wherein the relocation candidate list is based on a preference derived from mapped LUN tier properties.

14. The system of claim 9, wherein the relocation candidate list is based on filtering out a slices with a no relocation configuration.

15. The system of claim 9, wherein the relocation candidate list is based on matching slices to tiers starting with the highest tier.

16. The system of claim 9, wherein the relocation candidate list is based on matching slices to higher tiers before lower tiers.