Storage management apparatus, method and program

1. A storage management apparatus communicable with a plurality of edge servers each including a storage part storing data and access log information to the data, the storage management apparatus comprising:

a controller comprising a hardware processor configured to:

acquire the access log information from each of the edge servers;

determine, based on the acquired access log information, whether a state of access to the data stored in the storage part meets a preset criterion with respect to each of the edge servers; and

select, as a transfer target, data in the state of access which is decided as failing to meet the criterion, and to transfer the data to another storage part different from the storage part in which the data is stored,

wherein the criterion includes an ID of first sensing data which requires real-time processing and is excluded from the transfer target,

the controller is further configured to exclude the first sensing data which requires real-time processing from the transfer target based on the ID of the first sensing data, and

the controller is further configured to select, as a transfer target, second sensing data which does not require real-time processing among sensing data in the state of access which is decided as failing to meet the criterion, and

wherein when the plurality of edge servers are communicable with a cloud server via a network, the hardware processor is further configured to:

select a storage part which the cloud server includes, as the another storage part; and

transfer the data of the transfer target to the selected another storage part.

2. The storage management apparatus of claim 1 , wherein the hardware processor is further configured to:

acquire information relating to a state of use of a storage area with respect to each of the storage parts included in the edge servers;

select the another storage part from among the storage parts of the edge servers, based on the acquired information relating to the state of use of the storage area; and

transfer the data of the transfer target to the selected another storage part.

3. The storage management apparatus of claim 1 , wherein the hardware processor is further configured to:

select a storage part which the storage management apparatus includes, as the another storage part; and

transfer the data of the transfer target to the selected another storage part.

4. The storage management apparatus of claim 1 , wherein the hardware processor is further configured to select, as the another storage part, a storage medium with a lower access speed than the storage part in which the data of the transfer target is stored.

5. The storage management apparatus of claim 1 , wherein the hardware processor is further configured to measure an elapsed time from a time point of storage or from a latest access by a predetermined data unit with respect to the data stored in the storage part of each of the edge servers, and to decide that the criterion is not met when the elapsed time from the time point of storage or from the latest access exceeds a second threshold.

6. The storage management apparatus of claim 1 , wherein the hardware processor is further configured to decide whether the state of access to the data stored in the storage part of the edge server meets the preset criterion, by using at least one of identification information of the edge server that is to be set as a decision target, identification information of the data that is to be set as a decision target, a period that is to be set as a decision target, and a time frame length that is to be set as a decision unit, each of which is designated by the preset criterion.

7. The storage management apparatus of claim 1 , wherein the hardware processor is further configured to decide whether the state of access to the data stored in the storage part of the edge server meets the preset criterion, by using at least one of identification information of the edge server that is to be excluded from a decision target, identification information of the data that is to be excluded from a decision target, and a period that is to be excluded from a decision target, each of which is designated by the preset criterion.

8. A storage management method executed by a storage management apparatus communicable with a plurality of edge servers each including a storage part storing data and access log information to the data, the storage management method comprising:

acquiring the access log information from each of the edge servers;

determining, based on the acquired access log information, whether a state of access to the data stored in the storage part meets a preset criterion with respect to each of the edge servers; and

selecting, as a transfer target, data in the state of access which is decided as failing to meet the criterion, and to transfer the data to another storage part different from the storage part in which the data is stored,

wherein the criterion includes an ID of first sensing data which requires real-time processing and is excluded from the transfer target,

said determining comprises excluding the first sensing data which requires real-time processing from the transfer target based on the ID of the first sensing data, and

said selecting comprises selecting, as a transfer target, second sensing data which does not require real-time processing among sensing data in the state of access which is decided as failing to meet the criterion, and

wherein when the plurality of edge servers are communicable with a cloud server via a network, the storage management method further comprises:

selecting a storage part which the cloud server includes, as the another storage part; and

transferring the data of the transfer target to the selected another storage part.

9. A non-transitory computer readable medium storing a program causing a computer to execute a storage management method for a storage management apparatus communicable with a plurality of edge servers each including a storage part storing data and access log information to the data, the storage management method comprising:

acquiring the access log information from each of the edge servers;

determining, based on the acquired access log information, whether a state of access to the data stored in the storage part meets a preset criterion with respect to each of the edge servers; and

selecting, as a transfer target, data in the state of access which is decided as failing to meet the criterion, and to transfer the data to another storage part different from the storage part in which the data is stored,

wherein the criterion includes an ID of first sensing data which requires real-time processing and is excluded from the transfer target,

said determining comprises excluding the first sensing data which requires real-time processing from the transfer target based on the ID of the first sensing data, and

said selecting comprises selecting, as a transfer target, second sensing data which does not require real-time processing among sensing data in the state of access which is decided as failing to meet the criterion, and

wherein when the plurality of edge servers are communicable with a cloud server via a network, the storage management method further comprises:

selecting a storage part which the cloud server includes, as the another storage part; and

transferring the data of the transfer target to the selected another storage part.

10. The storage management apparatus of claim 1 , wherein the controller is further configured to count a number of accesses by a predetermined data unit with respect to the data stored in the storage part of each of the edge servers, and to decide that the criterion is not met when a total of the number of accesses in a latest first period is less than a first threshold.