Bucketized multi-index low-memory data structures

1. A method for generating and storing a data structure for maintaining a cache supporting compression and a cache-wide deduplication, comprising:

generating data structures with fixed size memory regions configured to hold multiple signatures as keys, wherein the number of the fixed size memory regions is bounded;

generating a first mapping from short-length signatures to a storage location and a quantized length measure on a cache storage device;

retrieving metadata and cache page content using a single input/output operation;

validating a correctness of a full value of one or more hash functions of uncompressed cache page content using the metadata;

generating a second mapping from the short-length signatures to entries in the first mapping, wherein one or more pointers to the entries in the first mapping are stored in a non-transitory computer readable storage medium,

wherein the first and second mappings are statically sized, relative to memory allocated and a number of contents, d-left hash tables with zero internal pointer overhead, wherein the statically sized d-left hash tables are never resized or reallocated; and

verifying whether the cached page content corresponds to a full-length original logical block address (LBA) using the metadata.

2. The method as recited in claim 1 , wherein the storage location information and the quantized length measure information is stored in a compressed format.

3. The method as recited in claim 1 , wherein the cache page content is stored in a compressed format.

4. The method as recited in claim 1 , wherein unused contiguous regions on the cache device of a predetermined length are allocated.

5. The method as recited in claim 1 , wherein the pointer to the entries in the first mapping is stored with a lower number of bits than a memory pointer.

6. The method as recited in claim 5 , wherein a bounded-length search is employed to locate a matching entry.

7. A system for generating and storing a data structure for maintaining a cache supporting compression and a cache-wide deduplication, comprising:

one or more data structures with fixed size memory regions configured to hold multiple signatures as keys, wherein the number of the fixed size memory regions is bounded;

a mapping generator configured to generate a first mapping from short-length signatures to a storage location and a quantized length measure on a cache storage device, and to generate a second mapping from the short-length signatures to entries in the first mapping, wherein one or more pointers to the entries in the first mapping are stored,

wherein the first and second mappings are statically sized, relative to memory allocated and a number of contents, d-left hash tables with zero internal pointer overhead, wherein the statically sized d-left hash tables are never resized or reallocated;

a content retrieval module configured to retrieve metadata and cache page content using a single input/output operation;

a validation module configured to validate a correctness of a full value of one or more hash functions of uncompressed cache page content using the metadata; and

a verification module configured to verify whether the cached page content corresponds to a full-length original logical block address (LBA) using the metadata.

8. The system as recited in claim 7 , wherein the storage location information and the quantized length measure information is stored in a compressed format.

9. The system as recited in claim 7 , wherein the cache page content is stored in a compressed format.

10. The system as recited in claim 7 , wherein unused contiguous regions on the cache device of a predetermined length are allocated.

11. The system as recited in claim 7 , wherein the pointer to the entries in the first mapping is stored with a lower number of bits than a memory pointer.

12. The system as recited in claim 11 , wherein a bounded-length search is employed to locate a matching entry.