Patent ID: 8990502
Filing Date: 2015-03-24
Classification: G06F,Y02D

Abstract:
1. A method of writing data units to a storage device, the method comprising: caching the data units in a first level cache by logical address to form sorted data units in the first level cache; handing over a group (G sorting, by logical address, data units of multiple groups (G providing a mapping table to the logical address of the data units to a physical address of the block the data units residing in the second level cache; and writing the sorted data units of the multiple groups to the storage device; when caching a new data unit in the first level cache, verifying whether the new data unit represents an update to a data unit currently residing in the second level cache by comparing a logical address of the new data unit to the logical addresses of the data units residing in the second level cache; and in the event the new data unit is found to be the update of the data unit currently residing in the second level cache, invalidating the data unit currently residing in the second level cache; wherein the removal of the data unit currently residing in the second level cache from the second level cache due to the update of the new data unit is handled by a mapping table update; and wherein the block is removed from the second level cache when all still valid data units in the block have been written to the storage device.