Quality of swaps of data storage volumes
AssigneeEMC Corporation
InventorsRuben Michel, Tao Kai Lam, David W. Desroches
Life of this patent
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Abstract
A method checks a swap's quality. The method includes finding an upper bound for reductions to a disk's seek time or total access time. The reductions are caused by swapping single storage volumes of the disk, which is in a preselected state, with an external storage volume. The method also includes finding a reduction to the seek time or total access time produced by swapping one storage volume of the disk with a selected external storage volume and comparing the found reduction to the upper bound.
Claims37
A method of checking a swap's quality, comprising:
- finding an upper bound for reductions to one of a seek time and a total access time, each reduction caused by swapping a physical storage volume of a disk in a preselected state with an external storage volume;
- determining a reduction to the one of a seek time and a total access time produced by swapping one storage volume of the disk in the preselected state with a selected external storage volume;
- and
- comparing the determined reduction to the upper bound.
A method of swapping physical storage volumes, comprising:
- finding a size of a reduction to one of a seek time and a total access time of a physical disk, the reduction being produced by swapping a selected storage volume of the disk with a selected external storage volume;
- and
- performing the swap in response to the reduction being at least as large as a preselected percentage of a reduction to the one of a seek time and a total access time produced by a swap of an external reference storage volume with a storage volume of the disk.
A program storage medium storing computer executable instructions for a method of checking a swap's quality that causes a computer to:
- find an upper bound for reductions to one of a seek time and a total access time, each reduction caused by swapping a physical storage volume of a disk in a preselected state with an external storage volume;
- determine a reduction to the one of a seek time and a total access time produced by swapping one storage volume of the disk in the preselected state with a selected external storage volume;
- and
- compare the determined reduction to the upper bound.
A program storage medium storing executable instructions for a method of swapping physical storage volumes, the instructions causing a computer to:
- find a size of a reduction to a one of a seek time and a total access time of a physical disk, the reduction being produced by swapping a selected storage volume of the disk with a selected external storage volume;
- and
- perform the swap in response to the reduction being at least as large as a preselected percentage of a reduction to the one of a seek time and a total access time that is produced by a swap of an external reference storage volume with a storage volume of the disk.
A system for swapping physical storage volumes, comprising:
- means for finding a size of a seek time reduction of a physical disk, the reduction being produced by swapping a selected storage volume of the disk with an external storage volume;
- and
- means for performing a swap in response to the reduction being at least as large as a preselected percentage of a seek time reduction produced by a swap of an external reference storage volume with a storage volume of the disk.
Dependencies are inferred from the claim text.