Storage tiering with efficient allocation of redundant data
Described is a system that allows for the efficient management of reallocating data between tiers of an automated storage tiering system. In certain configurations, protected data that is stored within the storage system may include a user data portion and a redundant data portion. Accordingly, to conserve space on higher storage tiers, the system may separate user data from the redundant data when reallocating data between tiers. For example, the system may only allocate the user data portion to higher storage tiers thereby conserving the space that would otherwise be taken by the redundant data, which remains, or is demoted to a lower tier. Moreover, the reallocation may occur during scheduled reallocation cycles, and accordingly, the reallocation of the separated protected data may occur without any additional tiering overhead.
1. A computer-implemented method, comprising:
storing protected data in a first storage tier within a multi-tier storage configuration, wherein the protected data comprises usage data and redundant data, wherein each of a plurality of storage tiers in the multi-tier storage configuration has a different level of performance and capacity;
determining a first set of usage characteristics of the protected data while the protected data is stored in the first storage tier, wherein a reference that links the redundant data and the usage data in the first storage tier is stored; and
in response to determining that the usage data and the redundant data of the protected data is stored together on the first storage tier, performing a first data reallocation cycle that promotes or demotes the protected data within the multi-tier storage configuration based on the determined set of usage characteristics, wherein when the protected data is promoted, only the usage data of the protected data is moved to a second storage tier that is a higher tier than the first storage tier within the multi-tier storage configuration and the redundant data remains on the first storage tier, wherein the second storage tier has a higher performance and a lower storage capacity than the first storage tier, and wherein after the moving of the usage data to the second storage tier, the reference between the redundant data and the usage data is maintained.
2. The method of claim 1 , wherein when the protected data is demoted, the redundant data of the protected data is moved to a third storage tier that is a lower tier than the first storage tier within the multi-tier storage and the usage data remains on the first storage tier.
3. The method of claim 1 , wherein the first data reallocation cycle is performed in response to determining that the protected data is stored on the first storage tier, wherein the first storage tier is marked as a storage tier for reallocation based on a storage policy.
4. The method of claim 1 , wherein the redundant data comprises at least one of a mirror copy, a parity block, or a coding fragment.
5. The method of claim 1 , wherein the first set of usage characteristics of the protected data includes at least a duration of time since the protected data was last accessed.
6. The method of claim 1 , wherein the first set of usage characteristics of the protected data includes at least a frequency at which the protected data has been accessed while stored on the first storage tier.
7. A non-transitory computer-readable medium storing instructions which, when executed by one or more processors of a computing device, cause the computing device to perform operations comprising:
storing protected data in a first storage tier within a multi-tier storage configuration, wherein the protected data comprises usage data and redundant data, wherein each of a plurality of storage tiers in the multi-tier storage configuration has a different level of performance and capacity;
determining a first set of usage characteristics of the protected data while the protected data is stored in the first storage tier, wherein a reference that links the redundant data and the usage data in the first storage tier is stored; and
in response to determining that the usage data and the redundant data of the protected data is stored together on the first storage tier, performing a first data reallocation cycle that promotes or demotes the protected data within the multi-tier storage configuration based on the determined set of usage characteristics, wherein when the protected data is promoted, only the usage data of the protected data is moved to a second storage tier that is a higher tier than the first storage tier within the multi-tier storage configuration and the redundant data remains on the first storage tier, wherein the second storage tier has a higher performance and a lower storage capacity than the first storage tier, and wherein after the moving of the usage data to the second storage tier, the reference between the redundant data and the usage data is maintained.
8. The medium of claim 7 , wherein when the protected data is demoted, the redundant data of the protected data is moved to a third storage tier that is a lower tier than the first storage tier within the multi-tier storage and the usage data remains on the first storage tier.
9. The medium of claim 7 , wherein the redundant data comprises at least one of a mirror copy, a parity block, or a coding fragment.
10. The medium of claim 7 , wherein the first set of usage characteristics of the protected data includes at least a duration of time since the protected data was last accessed.
11. The medium of claim 7 , wherein the first set of usage characteristics of the protected data includes at least a frequency at which the protected data has been accessed while stored on the first storage tier.
12. A device, comprising:
a memory storing instructions; and
a processor coupled to an engine and the memory to execute the instructions from the memory, the processor being configured to perform operations, the operations comprising:
storing protected data in a first storage tier within a multi-tier storage configuration, wherein the protected data comprises usage data and redundant data, wherein each of a plurality of storage tiers in the multi-tier storage configuration has a different level of performance and capacity;
determining a first set of usage characteristics of the protected data while the protected data is stored in the first storage tier, wherein a reference that links the redundant data and the usage data in the first storage tier is stored; and
in response to determining that the usage data and the redundant data of the protected data is stored together on the first storage tier, performing a first data reallocation cycle that promotes or demotes the protected data within the multi-tier storage configuration based on the determined set of usage characteristics, wherein when the protected data is promoted, only the usage data of the protected data is moved to a second storage tier that is a higher tier than the first storage tier within the multi-tier storage configuration and the redundant data remains on the first storage tier, wherein the second storage tier has a higher performance and a lower storage capacity than the first storage tier, and wherein after the moving of the usage data to the second storage tier, the reference between the redundant data and the usage data is maintained.
13. The device of claim 12 , wherein when the protected data is wet demoted, the redundant data of the protected data is moved to a third storage tier that is a lower tier than the first storage tier within the multi-tier storage and the usage data remains on the first storage tier.
14. The device of claim 12 , wherein the first data reallocation cycle is performed in response to determining that the protected data is stored on the first storage tier, wherein the first storage tier is marked as a storage tier for reallocation.
15. The device of claim 12 , wherein the first set of usage characteristics of the protected data includes at least a duration of time since the protected data was last accessed.
16. The device of claim 12 , wherein the first set of usage characteristics of the protected data includes at least a duration of time since the protected data was last accessed.
17. The device of claim 12 , wherein the first set of usage characteristics of the protected data includes at least a frequency at which the protected data has been accessed while stored on the first storage tier.