User:StefanoZacchiroli/Content deduplication

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Some experiments on deduplicating contents at sub-file granularity.

Datasets

Linux kernel, Git repo

  • origin: git.kernel.org, on 2018-01-06
  • 1.653.941 content blobs, for a total of 19 GB (compressed)

Rabin fingerprints

test 1

Dataset: linux.git

Rabin fingerprint parameters:

  • prime: 3
  • window_size: 48 KB
  • min_block_size: 2 KB
  • avg_block_size: 8 KB
  • max_block_size: 64 KB

Results:

  • average chunk size (effective): 9.37 KB
  • original size (uncompressed): 55.89 GB
  • dedup chunk size (uncompressed): 19.87 GB (35.55%)

test 2

Dataset: linux.git

Rabin fingerprint parameters:

  • prime: 3
  • window_size: 48 KB
  • min_block_size: 512 B
  • avg_block_size: 2 KB
  • max_block_size: 8 KB

Results:

  • average chunk size (effective): 5.07 KB
  • original size (uncompressed): 55.89 GB
  • dedup chunk size (uncompressed): 16.19 GB (28.96%)

References