Storage device, data management method, and data management program

A data management method by a storage device including one or more nonvolatile memory packages including a nonvolatile recording medium capable of storing data and a storage controller that control storing of data with respect to the nonvolatile memory packages, the storage device configured to:

• compress data, via a processor included in the storage controller, according to a first compression algorithm, wherein the first compression algorithm is a high compression algorithm;
• compress data, via a flash memory package external to the storage controller, according to a second compression algorithm different from the first compression algorithm, wherein the second compression algorithm is a low compression algorithm, a plurality of flash memories included in the flash memory package, wherein a processing capacity of the storage controller is higher than a processing capacity of the flash memories;
• calculate an access frequency for a page of a plurality of pages stored in a virtual volume;
• determine if the calculated access frequency is equal to or higher than a predetermined value;
• select the second algorithm when the calculated access frequency is equal to or higher than a predetermined value, as a selected algorithm;
• compare the second algorithm to a selection algorithm stored in the nonvolatile recording medium;
• determine that the selection algorithm stored is not the second algorithm and register that information as a change selection algorithm;
• determine that an operation rate of the processor is lower than a predetermined setting value,
• change the selection algorithm stored in the nonvolatile recording medium to the selected algorithm;
• compress, by the flash memory package, the write data based on the selected algorithm;
• and
• store, by the flash memory package, the compressed write data in the nonvolatile memory package.

A non-transitory computer readable medium storing a data management program for controlling a computer that forms a storage controller that controls storing of data with respect to one or more nonvolatile memory packages including a nonvolatile recording medium capable of storing data, when executed by a processor, causes the processor to:

• compress data, via a processor included in the storage controller, according to a first compression algorithm, wherein the first compression algorithm is a high compression algorithm;
• compress data, via a flash memory package external to the storage controller, according to a second compression algorithm different from the first compression algorithm, wherein the second compression algorithm is a low compression algorithm, a plurality of flash memories included in the flash memory package, wherein a processing capacity of the storage controller is higher than a processing capacity of the flash memories;
• calculate an access frequency for a page of a plurality of pages stored in a virtual volume;
• determine if the calculated access frequency is equal to or higher than a predetermined value;
• select the second algorithm when the calculated access frequency is equal to or higher than a predetermined value, as a selected algorithm;
• compare the second algorithm to a selection algorithm stored in the nonvolatile recording medium;
• determine that the selection algorithm stored is not the second algorithm and register that information as a change selection algorithm;
• determine that an operation rate of the processor is lower than a predetermined setting value;
• change the selection algorithm stored in the nonvolatile recording medium to the selected algorithm;
• compress, by the flash memory package, the write data based on the selected algorithm;
• and
• store, by the flash memory package, the compressed write data in the nonvolatile memory package.