Repair: remove one of the bottlenecks

[commial]

Partially fix #157

This PR:

• add a performance test to measure the repair time
• clarify how the convert_to_archive main loop works
• avoid calling the read API for each byte, as this must be equivalent to call it with bigger buffer

In addition to the included tests, the resulting code has been checked to be working on quite large files (~100MB).

As a result:

group	post-fix	pre-fix
failsafe_multiple_layers_repair/Layers(0x0)/4194304	1.00 73.1±2.18ms 54.7 MB/sec	1.76 128.4±1.35ms 31.2 MB/sec
failsafe_multiple_layers_repair/Layers(COMPRESS)/4194304	1.00 5.1±0.13s 796.3 KB/sec	1.52 7.8±0.09s 523.3 KB/sec
failsafe_multiple_layers_repair/Layers(ENCRYPT | COMPRESS)/4194304	1.00 6.2±0.47s 663.8 KB/sec	1.45 8.9±0.37s 458.3 KB/sec
failsafe_multiple_layers_repair/Layers(ENCRYPT)/4194304	1.00 106.6±6.92ms 37.5 MB/sec	5.68 605.4±130.34ms 6.6 MB/sec

As a bottleneck remains in how the CompressionLayerFailSafeReader, the modes which benefit the most from the fix are the EMPTY and ENCRYPT layer.

[github-actions]

Benchmark for c38bd80

Click to view benchmark

Test	Base	PR	%
chunk_size_decompress_mutilfiles_random/Layers(0x0)/1024	916.0±70.26ns	870.4±82.34ns	-4.98%
chunk_size_decompress_mutilfiles_random/Layers(0x0)/1048576	111.3±8.66µs	99.4±5.55µs	-10.69%
chunk_size_decompress_mutilfiles_random/Layers(0x0)/16777216	1781.7±27.48µs	1419.7±20.45µs	-20.32%
chunk_size_decompress_mutilfiles_random/Layers(0x0)/65536	7.8±0.53µs	7.1±0.69µs	-8.97%
chunk_size_decompress_mutilfiles_random/Layers(COMPRESS)/1024	855.9±470.13µs	741.4±406.66µs	-13.38%
chunk_size_decompress_mutilfiles_random/Layers(COMPRESS)/1048576	45.5±0.03ms	48.7±0.11ms	+7.03%
chunk_size_decompress_mutilfiles_random/Layers(COMPRESS)/16777216	241.8±0.33ms	259.0±0.47ms	+7.11%
chunk_size_decompress_mutilfiles_random/Layers(COMPRESS)/65536	9.8±5.64ms	10.5±5.99ms	+7.14%
chunk_size_decompress_mutilfiles_random/Layers(ENCRYPT | COMPRESS)/1024	1087.9±596.93µs	1187.2±671.74µs	+9.13%
chunk_size_decompress_mutilfiles_random/Layers(ENCRYPT | COMPRESS)/1048576	48.5±2.45ms	49.7±0.06ms	+2.47%
chunk_size_decompress_mutilfiles_random/Layers(ENCRYPT | COMPRESS)/16777216	515.8±0.31ms	534.4±0.39ms	+3.61%
chunk_size_decompress_mutilfiles_random/Layers(ENCRYPT | COMPRESS)/65536	8.0±0.01ms	8.3±0.01ms	+3.75%
chunk_size_decompress_mutilfiles_random/Layers(ENCRYPT)/1024	1837.7±799.95µs	1837.3±798.57µs	-0.02%
chunk_size_decompress_mutilfiles_random/Layers(ENCRYPT)/1048576	24.2±0.01ms	24.2±0.01ms	0.00%
chunk_size_decompress_mutilfiles_random/Layers(ENCRYPT)/16777216	354.0±0.11ms	353.7±0.09ms	-0.08%
chunk_size_decompress_mutilfiles_random/Layers(ENCRYPT)/65536	4.0±0.16ms	4.0±0.16ms	0.00%
failsafe_multiple_layers_repair/Layers(0x0)/4194304	79.3±0.83ms	N/A	N/A
failsafe_multiple_layers_repair/Layers(COMPRESS)/4194304	6.0±0.00s	N/A	N/A
failsafe_multiple_layers_repair/Layers(ENCRYPT | COMPRESS)/4194304	6.3±0.01s	N/A	N/A
failsafe_multiple_layers_repair/Layers(ENCRYPT)/4194304	112.0±0.64ms	N/A	N/A
reader_multiple_layers_multiple_block_size/Layers(0x0)/1024	197.4±24.17ns	184.3±16.58ns	-6.64%
reader_multiple_layers_multiple_block_size/Layers(0x0)/1048576	102.3±9.67µs	104.6±6.68µs	+2.25%
reader_multiple_layers_multiple_block_size/Layers(0x0)/16777216	1943.6±107.46µs	1823.6±54.41µs	-6.17%
reader_multiple_layers_multiple_block_size/Layers(0x0)/65536	6.3±0.78µs	6.5±0.69µs	+3.17%
reader_multiple_layers_multiple_block_size/Layers(COMPRESS)/1024	1968.4±2325.67ns	2.0±2.47µs	+1.61%
reader_multiple_layers_multiple_block_size/Layers(COMPRESS)/1048576	111.1±5.44µs	122.9±5.74µs	+10.62%
reader_multiple_layers_multiple_block_size/Layers(COMPRESS)/16777216	180.6±0.20ms	197.1±0.42ms	+9.14%
reader_multiple_layers_multiple_block_size/Layers(COMPRESS)/65536	139.9±166.02µs	151.2±180.08µs	+8.08%
reader_multiple_layers_multiple_block_size/Layers(ENCRYPT | COMPRESS)/1024	27.4±5.49µs	28.2±5.69µs	+2.92%
reader_multiple_layers_multiple_block_size/Layers(ENCRYPT | COMPRESS)/1048576	29.7±0.04ms	30.8±0.02ms	+3.70%
reader_multiple_layers_multiple_block_size/Layers(ENCRYPT | COMPRESS)/16777216	509.5±0.25ms	528.7±0.35ms	+3.77%
reader_multiple_layers_multiple_block_size/Layers(ENCRYPT | COMPRESS)/65536	1737.3±296.40µs	1803.5±310.74µs	+3.81%
reader_multiple_layers_multiple_block_size/Layers(ENCRYPT)/1024	20.3±1.68µs	20.3±1.69µs	0.00%
reader_multiple_layers_multiple_block_size/Layers(ENCRYPT)/1048576	21.4±0.02ms	21.4±0.01ms	0.00%
reader_multiple_layers_multiple_block_size/Layers(ENCRYPT)/16777216	351.2±0.10ms	351.0±0.05ms	-0.06%
reader_multiple_layers_multiple_block_size/Layers(ENCRYPT)/65536	1300.3±102.79µs	1300.4±103.01µs	+0.01%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(0x0)/1024	745.4±40.73ns	717.6±33.40ns	-3.73%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(0x0)/1048576	116.7±10.00µs	94.5±3.55µs	-19.02%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(0x0)/16777216	1806.1±137.64µs	1415.6±14.71µs	-21.62%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(0x0)/65536	8.2±0.77µs	6.8±0.33µs	-17.07%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(COMPRESS)/1024	16.9±0.15µs	18.1±0.14µs	+7.10%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(COMPRESS)/1048576	14.9±0.09ms	16.1±0.04ms	+8.05%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(COMPRESS)/16777216	239.7±0.95ms	258.8±0.31ms	+7.97%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(COMPRESS)/65536	936.5±5.91µs	1011.0±5.46µs	+7.96%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(ENCRYPT | COMPRESS)/1024	35.0±0.15µs	36.3±0.14µs	+3.71%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(ENCRYPT | COMPRESS)/1048576	31.7±0.02ms	32.8±0.03ms	+3.47%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(ENCRYPT | COMPRESS)/16777216	515.6±0.28ms	535.5±3.50ms	+3.86%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(ENCRYPT | COMPRESS)/65536	1994.9±18.21µs	2.1±0.02ms	+5.27%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(ENCRYPT)/1024	24.5±0.34µs	24.5±0.27µs	0.00%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(ENCRYPT)/1048576	22.2±0.02ms	22.1±0.01ms	-0.45%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(ENCRYPT)/16777216	354.0±0.10ms	353.7±0.11ms	-0.08%
reader_multiple_layers_multiple_block_size_multifiles_linear/Layers(ENCRYPT)/65536	1389.7±3.78µs	1385.3±0.39µs	-0.32%
writer_multiple_layers_multiple_block_size/Layers(0x0)/1024	10.1±0.08µs	10.0±0.19µs	-0.99%
writer_multiple_layers_multiple_block_size/Layers(0x0)/1048576	10.0±0.30ms	9.8±0.28ms	-2.00%
writer_multiple_layers_multiple_block_size/Layers(0x0)/16777216	160.4±0.54ms	158.2±0.61ms	-1.37%
writer_multiple_layers_multiple_block_size/Layers(0x0)/65536	623.9±18.56µs	610.3±19.28µs	-2.18%
writer_multiple_layers_multiple_block_size/Layers(COMPRESS)/1024	16.6±0.46µs	16.0±0.41µs	-3.61%
writer_multiple_layers_multiple_block_size/Layers(COMPRESS)/1048576	22.8±0.54ms	21.9±0.50ms	-3.95%
writer_multiple_layers_multiple_block_size/Layers(COMPRESS)/16777216	658.3±2.46ms	622.8±1.35ms	-5.39%
writer_multiple_layers_multiple_block_size/Layers(COMPRESS)/65536	1028.9±18.15µs	984.9±16.18µs	-4.28%
writer_multiple_layers_multiple_block_size/Layers(ENCRYPT | COMPRESS)/1024	16.5±0.26µs	16.0±0.50µs	-3.03%
writer_multiple_layers_multiple_block_size/Layers(ENCRYPT | COMPRESS)/1048576	27.2±2.67ms	26.5±2.72ms	-2.57%
writer_multiple_layers_multiple_block_size/Layers(ENCRYPT | COMPRESS)/16777216	927.6±1.75ms	893.7±1.98ms	-3.65%
writer_multiple_layers_multiple_block_size/Layers(ENCRYPT | COMPRESS)/65536	1050.9±23.67µs	1004.7±20.61µs	-4.40%
writer_multiple_layers_multiple_block_size/Layers(ENCRYPT)/1024	33.3±0.09µs	33.2±0.26µs	-0.30%
writer_multiple_layers_multiple_block_size/Layers(ENCRYPT)/1048576	32.2±0.12ms	32.2±0.08ms	0.00%
writer_multiple_layers_multiple_block_size/Layers(ENCRYPT)/16777216	515.8±1.12ms	513.5±0.99ms	-0.45%
writer_multiple_layers_multiple_block_size/Layers(ENCRYPT)/65536	2.0±0.01ms	1998.1±5.66µs	-0.10%