Boosting decompression in the presence of reoccurring Huffman trees
For boosting decompression in the presence of reoccurring Huffman trees, a previous Huffman tree is used to decompress a new data block if a match is identified between a compacted description of the Huffman tree and a recently used Huffman tree compaction.
1. A method for boosting decompression in the presence of reoccurring Huffman trees by a processor device in a computing storage environment, the method comprising:
using a previous Huffman tree to decompress a new data block if a match is identified between a compacted description of the Huffman tree and a recently used Huffman tree compaction.
2. The method of claim 1 , further including comparing the compacted description of the Huffman tree to recently used Huffman tree compactions for identifying matches rather than reconstructing a Huffman tree from a header of a compressed block for each data block to avoid overhead of a Huffman tree reconstruction.
3. The method of claim 1 , further including checking the header of the compressed block to determine if the header indicates that the encoding is done with a dynamic Huffman tree.
4. The method of claim 3 , further including performing at least one of:
determining if a previous Huffman tree exists in memory for an Inflate operation prior to reading a compacted description of the previous Huffman tree if the header indicates that the encoding is done with the dynamic Huffman tree, and
comparing the compacted description of the previous Huffman tree to a compacted description in the header of a new data block if the previous Huffman tree exists in the memory for the Inflate operation.
5. The method of claim 1 , further including performing at least one of:
preparing a new Huffman tree according to the header and maintaining a reference of a compacted description of the header of a new data block, and
storing a length of the tree compaction while preparing the new Huffman tree.
6. The method of claim 1 , further including performing at least one of:
decompacting a Huffman tree of a tree compaction, and
comparing the length of the tree compaction with a same number of bits from a designated location in the header of a new data block for ensuring the matching is exact and returning any mismatches for any two non-identical Huffman trees.
7. The method of claim 1 , further including maintaining previous Huffman trees in cache and comparing a compaction of a new Huffman tree in the header to each one of compactions of the previous Huffman trees stored in the cache.
8. The method of claim 7 , further including preparing a data structure for a set of the compactions of the previous Huffman trees stored in the cache, wherein the data structure is used for identifying the matches.
9. A system for boosting decompression in the presence of reoccurring Huffman trees in a computing environment, comprising:
a processor device operable in the computing environment, wherein processor device:
uses a previous Huffman tree to decompress a new data block if a match is identified between a compacted description of the Huffman tree and a recently used Huffman tree compaction.
10. The system of claim 9 , wherein the processor device compares the compacted description of the Huffman tree to recently used Huffman tree compactions for identifying matches rather than reconstructing a Huffman tree from a header of a compressed block for each data block to avoid overhead of a Huffman tree reconstruction.
11. The system of claim 9 , wherein the processor device checks the header of the compressed block to determine if the header indicates that the encoding is done with a dynamic Huffman tree.
12. The system of claim 11 , wherein the processor device performs at least one of:
determining if a previous Huffman tree exists in memory for an Inflate operation prior to reading a compacted description of the previous Huffman tree if the header indicates that the encoding is done with the dynamic Huffman tree, and
comparing the compacted description of the previous Huffman tree to a compacted description in the header of a new data block if the previous Huffman tree exists in the memory for the Inflate operation.
13. The system of claim 9 , wherein the processor device performs at least one of:
preparing a new Huffman tree according to the header and maintaining a reference of a compacted description of the header of a new data block, and
storing a length of the tree compaction while preparing the new Huffman tree.
14. The system of claim 9 , wherein the processor device performs at least one of:
decompacting a Huffman tree of a tree compaction, and
comparing the tree compaction with a given length with a same number of bits from a designated location in the header of a new data block for ensuring the matching is exact,
maintaining previous Huffman trees in cache and comparing a compaction of a new Huffman tree in the header to each one of compactions of the previous Huffman trees stored in the cache, and
prepares a data structure for a set of the compactions of the previous Huffman trees stored in the cache, wherein the data structure is used for identifying the matches.
15. A computer program product for boosting decompression in the presence of reoccurring Huffman trees in a computing environment by a processor device, the computer program product comprising a non-transitory computer-readable storage medium having computer-readable program code portions stored therein, the computer-readable program code portions comprising:
a first executable portion that uses a previous Huffman tree to decompress a new data block if a match is identified between a compacted description of the Huffman tree and a recently used Huffman tree compaction.
16. The computer program product of claim 15 , further including a second executable portion that compares the compacted description of the Huffman tree to recently used Huffman tree compactions for identifying matches rather than reconstructing a Huffman tree from a header of a compressed block for each data block to avoid overhead of a Huffman tree reconstruction.
17. The computer program product of claim 15 , further including a second executable portion that checks the header of the compressed block to determine if the header indicates that the encoding is done with a dynamic Huffman tree.
18. The computer program product of claim 17 , further including a third executable portion that performs at least one of:
decompacting a Huffman tree of a tree compaction, and
comparing the tree compaction with a given length with a same number of bits from a designated location in the header of a new data block for ensuring the matching is exact,
preparing a new Huffman tree according to the header and maintaining a reference of a compacted description of the header of a new data block, and
storing a length of the tree compaction while preparing the new Huffman tree.
19. The computer program product of claim 15 , further including a second executable portion that performs at least one of:
decompacting a Huffman tree for determining a length of a tree compaction, wherein the length of the tree compaction of a previous Huffman tree is stored,
comparing the tree compaction with a given length with a same number of bits from a designated location in the header of a new data block for ensuring the matching is exact, and
maintaining previous Huffman trees in cache and comparing a compaction of a new Huffman tree in the header to each one of compactions of the previous Huffman trees stored in the cache.
20. The computer program product of claim 15 , further including a second executable portion that prepares a data structure for a set of the compactions of the previous Huffman trees stored in the cache, wherein the data structure is used for identifying the matches.