Mirrored cache protection

摘要

Methods of protecting cache data are provided. For example, various methods are described that assist in handling dirty write data cached in memory by duplication into other locations to protect against data loss. One method includes caching a data item from a data source in a first cache device. The data item cached in the first cache device is designated with a first designation. In response to the data item being modified by a data consumer, the designation of the data item in the first cache device is re-assigned from the first designation to a second designation, and the data item with the second designation is copied to a second cache device.

主权项

1. A method of cache data redundancy, comprising:
providing a plurality of cache devices, wherein each of the plurality of cache devices is partitioned into a first allocated area and a second allocated area, the first allocated area being used for storing data items that are in an unmodified form and the second allocated area being used for storing data items that are in a modified form; copying a data item from a data source to the first allocated area in one of the plurality of cache devices, the data item being in the unmodified form; in response to the data item being modified by a data consumer, (a) logically removing the data item from the first allocated area of one of the plurality of cache devices; (b) copying the data item in the modified form to the second allocated area in one of the plurality of cache devices; and transferring the data item in the modified form from the second allocated area of one of the plurality of cache devices to the data source, in response to the transferring to the data source, copying the data item in the modified form from the second allocated area of the one of the plurality of cache devices to the first allocated area of one of the plurality of cache devices.