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118 commits

Author SHA1 Message Date
Moinak Ghosh
c6da2325e3 Allow SKEIN to be used as a Global Dedupe chunk lookup hash. 2013-05-04 15:59:29 +05:30
Moinak Ghosh
0cf94c308a Add a qsort variant optimized for integers and use in global dedupe. 
Cleanup LZMA CRC64/32 declarations and add a header.
Fix heapq header.
 2013-05-03 22:06:55 +05:30
Moinak Ghosh
c43e99f422 Use openmp parallelism always for chunk hash computation during Global Dedupe. 2013-05-02 23:24:43 +05:30
Moinak Ghosh
120877348c Use SHA256 for Global Dedupe chunk lookup hash by default. 
Allow changing Global Dedupe chunk lookup hash via env variable.
 2013-05-02 00:05:05 +05:30
Moinak Ghosh
eae16b82d3 Fix issue #7. 
Ensure tempfile cleanup even with error abort.
 2013-05-01 18:01:17 +05:30
Moinak Ghosh
b23b5789fb Fix bugs and improve accuracy in Segmented Dedupe. 
Fix segment hashlist size computation.
Remove unnecessary sync of segment hashlist file writes.
Pass correct number of threads to index creation routine.
Add more error checks.
Handle correct positioning of segment hashlist file offset on write error.
Add missing semaphore signaling at dedupe abort points with global dedupe.
Use closer min-values sampling for improved segmented dedupe accuracy.
Update proper checksum info in README.
 2013-04-30 19:35:18 +05:30
Moinak Ghosh
074e265f70 Fix sizing of similarity hash buffer. 2013-04-26 22:36:14 +05:30
Moinak Ghosh
2f2fc23771 Tweak index size computation. 2013-04-26 19:21:11 +05:30
Moinak Ghosh
aed69b2d53 Add test cases for Global Deduplication. 
Update documentation and code comments.
Remove tempfile pathname after creation to ensure clean removal after process exit.
 2013-04-26 18:32:00 +05:30
Moinak Ghosh
75f62d6a36 Simplify segment lookup loop. 
Fix assertion.
 2013-04-26 10:56:29 +05:30
Moinak Ghosh
5bb028fe03 Change Segmented Dedupe flow to improve parallelism. 
Periodically sync writes to segcache file.
Use simple insertion sort for small numbers of elements.
 2013-04-25 23:42:32 +05:30
Moinak Ghosh
79a6e7f770 Capability to output data to stdout when compressing. 
Always use segmented similarity bases dedupe when using -G option in pipe mode.
Standardize on average 8MB segment size for segmented dedupe.
Fix hashtable sizing.
Some miscellaneous cleanups.
Update README with details of new features.
 2013-04-24 23:03:58 +05:30
Moinak Ghosh
6c5d8d9e18 Optimize index lookup for 8-byte keys. 
More cleanups.
 2013-04-24 19:49:43 +05:30
Moinak Ghosh
5d6ffd969d More tweaks to slightly improve segment dedupe efficiency. 
Use on average 8MB segments for all cases.
Some minor cleanps.
 2013-04-24 19:13:07 +05:30
Moinak Ghosh
eabd670790 Improve segment similarity detection and drastically reduce index size. 2013-04-23 23:15:32 +05:30
Moinak Ghosh
b32f4b3f9a Improve duplicate segment match detection. 2013-04-23 20:51:12 +05:30
Moinak Ghosh
6b7d883393 Tweak percentage intervals computation to improve segmented dedupe ratio. 
Avoid repeat processing of already processed segments.
 2013-04-23 18:53:56 +05:30
Moinak Ghosh
d29f125ca7 Clean up temp cache dir handling. 
Allow temp dir setting via specific env variable to point to fast devices like ramdisk,ssd.
 2013-04-22 22:57:31 +05:30
Moinak Ghosh
2c4024792a Several bugfixes. 
Avoid matching with self during hash lookup.
 2013-04-22 22:07:07 +05:30
Moinak Ghosh
6b23f6a73a Several fixes and optimizations. 2013-04-22 19:52:18 +05:30
Moinak Ghosh
c0b4aa0116 Many optimizations and changes to Segmented Global Dedupe. 
Use chunk hash based similarity matching rather than content based.
Use sorting to order hash buffer rather than min-heap for better accuracy.
Use fast CRC64 for similarity hash for speed and lower memory requirements.
 2013-04-21 18:11:16 +05:30
Moinak Ghosh
3b8a5813fd Many optimizations to segmented global dedupe. 
Use chunk hash based cumulative similarity matching instead of chunk content.
 2013-04-19 22:51:51 +05:30
Moinak Ghosh
2f6ccca6e5 Update usage text and add minor tweaks. 2013-04-18 22:55:49 +05:30
Moinak Ghosh
426c0d0bf2 Properly cleanup global dedupe state. 2013-04-18 21:36:36 +05:30
Moinak Ghosh
8ae571124d Complete implementation for Segmented Global Deduplication. 2013-04-18 21:26:24 +05:30
Moinak Ghosh
a22b52cf08 Work in progress changes for Segmented Global Deduplication. 2013-04-14 23:51:54 +05:30
Moinak Ghosh
50251107de Work in progress changes for Segmented Global Deduplication. 2013-04-09 22:23:51 +05:30
Moinak Ghosh
3d7a179a77 Work in progress changes for scalable segmented global deduplication. 
Allow user-specified environment setting to control in-memory index size.
 2013-04-06 15:15:27 +05:30
Moinak Ghosh
c357452079 Implement global dedupe in pipe mode. 
Update hash index calculations to use upto 75% memavail when file size is not known.
Use little-endian nonce format for Salsa20.
 2013-03-29 15:18:25 +05:30
Moinak Ghosh
19b304f30c Add global index cleanup function. 
Fix location of sem_wait().
More comments.
 2013-03-25 21:04:16 +05:30
Moinak Ghosh
fbf4658635 Implement Global Deduplication. 2013-03-24 23:21:17 +05:30
Moinak Ghosh
876796be5c Work in progress changes for global dedupe. 2013-03-21 22:00:38 +05:30
Moinak Ghosh
b7fdeb08bc Work in progress global dedupe changes. 2013-03-20 22:47:03 +05:30
Moinak Ghosh
f2806d4ffa Work in progress global dedupe changes. 2013-03-19 20:13:44 +05:30
Moinak Ghosh
f8f23e5200 Major License text cleanup. 2013-03-07 20:26:48 +05:30
Moinak Ghosh
e16b408061 Move Scrypt helper function out of AES module. 
Fix a compiler warning.
 2013-03-03 21:55:59 +05:30
Moinak Ghosh
5f6217bb1f Add lookup and insert functionality for global index. 
Make global dedupe code buildable.
 2013-02-21 23:07:07 +05:30
Moinak Ghosh
6badbcaea7 Make global dedupe bits buildable and fix errors. 
Rename Adaptive compression type constants to avoid conflict with global constants.
 2013-02-17 21:05:40 +05:30
Moinak Ghosh
7386f82a4f Work in progress global dedupe. 2013-02-16 23:33:06 +05:30
Moinak Ghosh
f89473d29c Fixes for issues/warnings reported in issue #4. 2013-02-15 22:53:17 +05:30
Moinak Ghosh
24d62bfde9 Global dedupe work in progress. 2013-02-14 23:10:53 +05:30
Moinak Ghosh
1eae57c8a2 Starting changes for single-file global dedupe. 2013-02-12 21:53:04 +05:30
Moinak Ghosh
3e1737b4ab Use OpenMP parallelism when computing xxHashes for chunks. 2013-02-02 09:27:58 +05:30
Moinak Ghosh
af4c6e1d84 Reduce dedupe hash table collisions by half. 2013-01-31 00:38:41 +05:30
Moinak Ghosh
3d8f3ada1c Improve Deduplication performance by another 95%. 
Start sliding window scanning near minimum chunk size boundaries to avoid scanning whole chunk.
 2013-01-30 22:41:13 +05:30
Moinak Ghosh
5c8704c5bb Improve Deduplication throughtput by 90%. 
Use SSE4 register as sliding window for default 16-byte window size.
Use local variable for sliding window position to avoid spurios memory access in non-SIMD case.
Avoid computing breakpoint check value if processed length < minimum block length.
 2013-01-22 15:54:42 +05:30
Moinak Ghosh
3888c8d316 Many optimization tweaks 
Optimize Rabin Deduplication and Bsdiff
Vectorize XXHash using SE4
 2013-01-20 22:02:26 +05:30
Moinak Ghosh
455c8107d5 Use pre-increment for shorter instruction length and slight speed. 2013-01-17 22:54:30 +05:30
Moinak Ghosh
39dbc4be43 Implement algo-specific minimum distance match for Delta Compression. 2013-01-14 13:20:07 +05:30
Moinak Ghosh
d49a088eea Fixes and performance improvements for Dedupe Delta Compression 
Avoid using fingerprints in minhash computation and fix write amplification
Modify min-heap to use 64bit values
Improve bsdiff performance
Fix pointer comparison in bsdiff
Use 32bit offsets in bsdiff to reduce memory usage
Improve Zero RLE Encoder performance
Add more buffer overflow checks in Zero RLE Decoder
 2013-01-13 22:04:59 +05:30