Title: Refactor `dill` logic
Author: mariosasko (COLLABORATOR)
State: closed
Created: 2023-11-27T20:01:25Z

Refactor the `dill` logic to make it easier to maintain (and fix some issues along the way)

It makes the following improvements to the serialization API:
* consistent order of a `dict`'s keys
* support for hashing `torch.compile`-ed modules and functions
* deprecates `datasets.fingerprint.hashregister` as the `hashregister`-ed reducers are never invoked anyways (does not support nested data as `pickle`/`dill` do)


~~TODO: optimize hashing of `pa.Table` and `datasets.table.Table`~~ The `pa_array.to_string` approach is faster for large arrays because it outputs the first 10 and last 10 elements (by default). The problem is that this can produce identical hashes for non-identical arrays if their differing elements get ellipsed...
 
Fix https://github.com/huggingface/datasets/issues/6440, fix https://github.com/huggingface/datasets/issues/5839

Comments:
<details>
<summary>Show benchmarks</summary>

PyArrow==8.0.0

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.005490 / 0.011353 (-0.005863) | 0.003554 / 0.011008 (-0.007454) | 0.062183 / 0.038508 (0.023675) | 0.053093 / 0.023109 (0.029984) | 0.245370 / 0.275898 (-0.030528) | 0.271637 / 0.323480 (-0.051842) | 0.002997 / 0.007986 (-0.004989) | 0.002811 / 0.004328 (-0.001517) | 0.047874 / 0.004250 (0.043623) | 0.039673 / 0.037052 (0.002620) | 0.253219 / 0.258489 (-0.005271) | 0.280438 / 0.293841 (-0.013403) | 0.028393 / 0.128546 (-0.100153) | 0.010914 / 0.075646 (-0.064732) | 0.207491 / 0.419271 (-0.211781) | 0.037565 / 0.043533 (-0.005968) | 0.252382 / 0.255139 (-0.002757) | 0.272204 / 0.283200 (-0.010995) | 0.019007 / 0.141683 (-0.122676) | 1.099767 / 1.452155 (-0.352388) | 1.173220 / 1.492716 (-0.319496) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.098777 / 0.018006 (0.080771) | 0.325912 / 0.000490 (0.325422) | 0.000214 / 0.000200 (0.000014) | 0.000051 / 0.000054 (-0.000003) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.018815 / 0.037411 (-0.018596) | 0.070031 / 0.014526 (0.055506) | 0.075395 / 0.176557 (-0.101162) | 0.122633 / 0.737135 (-0.614502) | 0.077621 / 0.296338 (-0.218718) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.290830 / 0.215209 (0.075621) | 2.869214 / 2.077655 (0.791559) | 1.507337 / 1.504120 (0.003217) | 1.351391 / 1.541195 (-0.189804) | 1.386642 / 1.468490 (-0.081848) | 0.570318 / 4.584777 (-4.014459) | 2.423442 / 3.745712 (-1.322270) | 2.897812 / 5.269862 (-2.372050) | 1.796458 / 4.565676 (-2.769219) | 0.063649 / 0.424275 (-0.360626) | 0.005038 / 0.007607 (-0.002570) | 0.357819 / 0.226044 (0.131774) | 3.535478 / 2.268929 (1.266549) | 1.831764 / 55.444624 (-53.612861) | 1.545035 / 6.876477 (-5.331442) | 1.585919 / 2.142072 (-0.556154) | 0.643333 / 4.805227 (-4.161894) | 0.120319 / 6.500664 (-6.380345) | 0.043031 / 0.075469 (-0.032438) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.981155 / 1.841788 (-0.860633) | 12.136069 / 8.074308 (4.061760) | 10.579923 / 10.191392 (0.388531) | 0.152963 / 0.680424 (-0.527461) | 0.014783 / 0.534201 (-0.519418) | 0.289177 / 0.579283 (-0.290106) | 0.271784 / 0.434364 (-0.162580) | 0.322381 / 0.540337 (-0.217956) | 0.420034 / 1.386936 (-0.966902) |

</details>
PyArrow==latest

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.005315 / 0.011353 (-0.006038) | 0.003584 / 0.011008 (-0.007424) | 0.048596 / 0.038508 (0.010088) | 0.055940 / 0.023109 (0.032830) | 0.277687 / 0.275898 (0.001789) | 0.301545 / 0.323480 (-0.021935) | 0.004150 / 0.007986 (-0.003836) | 0.002699 / 0.004328 (-0.001629) | 0.047661 / 0.004250 (0.043410) | 0.040618 / 0.037052 (0.003565) | 0.279173 / 0.258489 (0.020684) | 0.306105 / 0.293841 (0.012264) | 0.030099 / 0.128546 (-0.098447) | 0.010784 / 0.075646 (-0.064862) | 0.057418 / 0.419271 (-0.361853) | 0.032632 / 0.043533 (-0.010901) | 0.276064 / 0.255139 (0.020925) | 0.307194 / 0.283200 (0.023995) | 0.017416 / 0.141683 (-0.124267) | 1.107749 / 1.452155 (-0.344406) | 1.161104 / 1.492716 (-0.331612) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.102395 / 0.018006 (0.084389) | 0.316933 / 0.000490 (0.316443) | 0.000246 / 0.000200 (0.000046) | 0.000042 / 0.000054 (-0.000012) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.022833 / 0.037411 (-0.014579) | 0.069372 / 0.014526 (0.054846) | 0.082139 / 0.176557 (-0.094418) | 0.121666 / 0.737135 (-0.615469) | 0.084039 / 0.296338 (-0.212300) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.298775 / 0.215209 (0.083566) | 2.973898 / 2.077655 (0.896244) | 1.614436 / 1.504120 (0.110316) | 1.476112 / 1.541195 (-0.065083) | 1.502031 / 1.468490 (0.033541) | 0.580626 / 4.584777 (-4.004151) | 2.493428 / 3.745712 (-1.252285) | 2.931050 / 5.269862 (-2.338811) | 1.823603 / 4.565676 (-2.742073) | 0.064736 / 0.424275 (-0.359539) | 0.004963 / 0.007607 (-0.002644) | 0.355096 / 0.226044 (0.129052) | 3.522801 / 2.268929 (1.253872) | 1.968690 / 55.444624 (-53.475935) | 1.698624 / 6.876477 (-5.177853) | 1.714166 / 2.142072 (-0.427906) | 0.681734 / 4.805227 (-4.123493) | 0.118940 / 6.500664 (-6.381724) | 0.041960 / 0.075469 (-0.033509) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.985311 / 1.841788 (-0.856476) | 12.785393 / 8.074308 (4.711085) | 11.289459 / 10.191392 (1.098067) | 0.145297 / 0.680424 (-0.535127) | 0.016125 / 0.534201 (-0.518076) | 0.289445 / 0.579283 (-0.289838) | 0.278974 / 0.434364 (-0.155390) | 0.322456 / 0.540337 (-0.217881) | 0.418218 / 1.386936 (-0.968718) |

</details>
</details>

![](https://cml.dev/watermark.png#66cef090c55d3561412468d94cb545b47fb000fb "CML watermark")


_The documentation is not available anymore as the PR was closed or merged._

<details>
<summary>Show benchmarks</summary>

PyArrow==8.0.0

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.005142 / 0.011353 (-0.006211) | 0.004180 / 0.011008 (-0.006829) | 0.062647 / 0.038508 (0.024139) | 0.055072 / 0.023109 (0.031962) | 0.254681 / 0.275898 (-0.021217) | 0.282650 / 0.323480 (-0.040830) | 0.003950 / 0.007986 (-0.004035) | 0.002862 / 0.004328 (-0.001466) | 0.048420 / 0.004250 (0.044170) | 0.038447 / 0.037052 (0.001394) | 0.258160 / 0.258489 (-0.000329) | 0.288596 / 0.293841 (-0.005245) | 0.027898 / 0.128546 (-0.100648) | 0.011165 / 0.075646 (-0.064482) | 0.206844 / 0.419271 (-0.212427) | 0.036312 / 0.043533 (-0.007221) | 0.257957 / 0.255139 (0.002819) | 0.277387 / 0.283200 (-0.005812) | 0.018205 / 0.141683 (-0.123478) | 1.109870 / 1.452155 (-0.342284) | 1.175005 / 1.492716 (-0.317712) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.096692 / 0.018006 (0.078686) | 0.307463 / 0.000490 (0.306973) | 0.000218 / 0.000200 (0.000018) | 0.000042 / 0.000054 (-0.000012) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.018602 / 0.037411 (-0.018809) | 0.061489 / 0.014526 (0.046964) | 0.072936 / 0.176557 (-0.103620) | 0.119863 / 0.737135 (-0.617272) | 0.073983 / 0.296338 (-0.222355) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.291444 / 0.215209 (0.076235) | 2.849024 / 2.077655 (0.771369) | 1.533121 / 1.504120 (0.029001) | 1.402148 / 1.541195 (-0.139046) | 1.406397 / 1.468490 (-0.062094) | 0.564241 / 4.584777 (-4.020536) | 2.402052 / 3.745712 (-1.343660) | 2.772639 / 5.269862 (-2.497223) | 1.732342 / 4.565676 (-2.833334) | 0.062361 / 0.424275 (-0.361914) | 0.004945 / 0.007607 (-0.002662) | 0.355841 / 0.226044 (0.129797) | 3.426931 / 2.268929 (1.158003) | 1.865412 / 55.444624 (-53.579212) | 1.592628 / 6.876477 (-5.283849) | 1.662364 / 2.142072 (-0.479708) | 0.653278 / 4.805227 (-4.151949) | 0.118626 / 6.500664 (-6.382038) | 0.042961 / 0.075469 (-0.032508) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.956279 / 1.841788 (-0.885509) | 11.635540 / 8.074308 (3.561232) | 10.719590 / 10.191392 (0.528198) | 0.130015 / 0.680424 (-0.550409) | 0.014424 / 0.534201 (-0.519777) | 0.288135 / 0.579283 (-0.291148) | 0.270819 / 0.434364 (-0.163545) | 0.320238 / 0.540337 (-0.220099) | 0.421044 / 1.386936 (-0.965892) |

</details>
PyArrow==latest

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.005201 / 0.011353 (-0.006152) | 0.003467 / 0.011008 (-0.007541) | 0.048939 / 0.038508 (0.010431) | 0.051841 / 0.023109 (0.028732) | 0.273708 / 0.275898 (-0.002190) | 0.293491 / 0.323480 (-0.029988) | 0.004830 / 0.007986 (-0.003156) | 0.002696 / 0.004328 (-0.001632) | 0.047727 / 0.004250 (0.043476) | 0.041319 / 0.037052 (0.004266) | 0.273837 / 0.258489 (0.015348) | 0.309860 / 0.293841 (0.016019) | 0.029054 / 0.128546 (-0.099492) | 0.010410 / 0.075646 (-0.065237) | 0.058139 / 0.419271 (-0.361133) | 0.032682 / 0.043533 (-0.010850) | 0.273244 / 0.255139 (0.018105) | 0.291579 / 0.283200 (0.008380) | 0.018262 / 0.141683 (-0.123421) | 1.144590 / 1.452155 (-0.307565) | 1.202474 / 1.492716 (-0.290243) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.097110 / 0.018006 (0.079104) | 0.307344 / 0.000490 (0.306854) | 0.000229 / 0.000200 (0.000029) | 0.000045 / 0.000054 (-0.000009) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.022263 / 0.037411 (-0.015148) | 0.070140 / 0.014526 (0.055614) | 0.081251 / 0.176557 (-0.095306) | 0.120839 / 0.737135 (-0.616297) | 0.083312 / 0.296338 (-0.213026) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.297381 / 0.215209 (0.082172) | 2.895530 / 2.077655 (0.817875) | 1.608442 / 1.504120 (0.104322) | 1.476237 / 1.541195 (-0.064958) | 1.491306 / 1.468490 (0.022816) | 0.567272 / 4.584777 (-4.017505) | 2.463543 / 3.745712 (-1.282170) | 2.814764 / 5.269862 (-2.455098) | 1.725845 / 4.565676 (-2.839831) | 0.064149 / 0.424275 (-0.360126) | 0.004953 / 0.007607 (-0.002654) | 0.359629 / 0.226044 (0.133585) | 3.482414 / 2.268929 (1.213486) | 1.949897 / 55.444624 (-53.494727) | 1.677383 / 6.876477 (-5.199094) | 1.683655 / 2.142072 (-0.458418) | 0.645671 / 4.805227 (-4.159557) | 0.115612 / 6.500664 (-6.385053) | 0.041013 / 0.075469 (-0.034456) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.967843 / 1.841788 (-0.873945) | 12.376877 / 8.074308 (4.302569) | 10.988174 / 10.191392 (0.796782) | 0.134660 / 0.680424 (-0.545764) | 0.015801 / 0.534201 (-0.518400) | 0.288699 / 0.579283 (-0.290584) | 0.284887 / 0.434364 (-0.149477) | 0.322000 / 0.540337 (-0.218337) | 0.412360 / 1.386936 (-0.974576) |

</details>
</details>

![](https://cml.dev/watermark.png#148454d48b7c36507a283217c7c0e3bcc0539f75 "CML watermark")


<details>
<summary>Show benchmarks</summary>

PyArrow==8.0.0

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.005407 / 0.011353 (-0.005946) | 0.003496 / 0.011008 (-0.007512) | 0.062730 / 0.038508 (0.024222) | 0.051882 / 0.023109 (0.028773) | 0.244766 / 0.275898 (-0.031132) | 0.257963 / 0.323480 (-0.065516) | 0.002894 / 0.007986 (-0.005092) | 0.002567 / 0.004328 (-0.001761) | 0.048756 / 0.004250 (0.044506) | 0.039024 / 0.037052 (0.001971) | 0.247303 / 0.258489 (-0.011186) | 0.278341 / 0.293841 (-0.015500) | 0.026725 / 0.128546 (-0.101821) | 0.010577 / 0.075646 (-0.065069) | 0.210483 / 0.419271 (-0.208789) | 0.035230 / 0.043533 (-0.008303) | 0.246125 / 0.255139 (-0.009014) | 0.264039 / 0.283200 (-0.019160) | 0.019881 / 0.141683 (-0.121802) | 1.113475 / 1.452155 (-0.338679) | 1.149606 / 1.492716 (-0.343110) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.092946 / 0.018006 (0.074940) | 0.299985 / 0.000490 (0.299495) | 0.000215 / 0.000200 (0.000016) | 0.000050 / 0.000054 (-0.000005) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.018421 / 0.037411 (-0.018991) | 0.060531 / 0.014526 (0.046005) | 0.074459 / 0.176557 (-0.102098) | 0.120369 / 0.737135 (-0.616766) | 0.075505 / 0.296338 (-0.220833) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.289497 / 0.215209 (0.074288) | 2.783139 / 2.077655 (0.705485) | 1.482533 / 1.504120 (-0.021587) | 1.371013 / 1.541195 (-0.170182) | 1.379114 / 1.468490 (-0.089376) | 0.563953 / 4.584777 (-4.020824) | 2.389996 / 3.745712 (-1.355716) | 2.788067 / 5.269862 (-2.481795) | 1.751772 / 4.565676 (-2.813904) | 0.062680 / 0.424275 (-0.361595) | 0.004901 / 0.007607 (-0.002706) | 0.365193 / 0.226044 (0.139149) | 3.389181 / 2.268929 (1.120252) | 1.861659 / 55.444624 (-53.582965) | 1.558899 / 6.876477 (-5.317577) | 1.591079 / 2.142072 (-0.550993) | 0.648300 / 4.805227 (-4.156927) | 0.117486 / 6.500664 (-6.383178) | 0.041961 / 0.075469 (-0.033508) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.944391 / 1.841788 (-0.897396) | 11.500823 / 8.074308 (3.426515) | 10.580430 / 10.191392 (0.389038) | 0.142845 / 0.680424 (-0.537579) | 0.014305 / 0.534201 (-0.519896) | 0.290723 / 0.579283 (-0.288560) | 0.266206 / 0.434364 (-0.168158) | 0.325482 / 0.540337 (-0.214856) | 0.416224 / 1.386936 (-0.970712) |

</details>
PyArrow==latest

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.005363 / 0.011353 (-0.005990) | 0.003548 / 0.011008 (-0.007460) | 0.048704 / 0.038508 (0.010196) | 0.051025 / 0.023109 (0.027916) | 0.273037 / 0.275898 (-0.002861) | 0.297148 / 0.323480 (-0.026332) | 0.003985 / 0.007986 (-0.004001) | 0.002739 / 0.004328 (-0.001590) | 0.048108 / 0.004250 (0.043857) | 0.040244 / 0.037052 (0.003191) | 0.277825 / 0.258489 (0.019336) | 0.303704 / 0.293841 (0.009863) | 0.029460 / 0.128546 (-0.099086) | 0.010428 / 0.075646 (-0.065218) | 0.057022 / 0.419271 (-0.362249) | 0.032711 / 0.043533 (-0.010822) | 0.274462 / 0.255139 (0.019323) | 0.293499 / 0.283200 (0.010299) | 0.018266 / 0.141683 (-0.123417) | 1.158049 / 1.452155 (-0.294106) | 1.170097 / 1.492716 (-0.322620) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.093412 / 0.018006 (0.075406) | 0.301538 / 0.000490 (0.301049) | 0.000222 / 0.000200 (0.000022) | 0.000051 / 0.000054 (-0.000003) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.021698 / 0.037411 (-0.015713) | 0.068735 / 0.014526 (0.054209) | 0.083010 / 0.176557 (-0.093546) | 0.127491 / 0.737135 (-0.609644) | 0.083005 / 0.296338 (-0.213333) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.298299 / 0.215209 (0.083090) | 2.894209 / 2.077655 (0.816554) | 1.597455 / 1.504120 (0.093335) | 1.472953 / 1.541195 (-0.068241) | 1.491553 / 1.468490 (0.023063) | 0.556566 / 4.584777 (-4.028211) | 2.419429 / 3.745712 (-1.326283) | 2.788706 / 5.269862 (-2.481156) | 1.759888 / 4.565676 (-2.805789) | 0.062535 / 0.424275 (-0.361740) | 0.004959 / 0.007607 (-0.002648) | 0.345226 / 0.226044 (0.119182) | 3.438539 / 2.268929 (1.169611) | 1.943842 / 55.444624 (-53.500782) | 1.661080 / 6.876477 (-5.215397) | 1.687632 / 2.142072 (-0.454440) | 0.639971 / 4.805227 (-4.165256) | 0.116012 / 6.500664 (-6.384652) | 0.041723 / 0.075469 (-0.033746) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.965143 / 1.841788 (-0.876645) | 12.086547 / 8.074308 (4.012238) | 10.708787 / 10.191392 (0.517395) | 0.129506 / 0.680424 (-0.550918) | 0.015254 / 0.534201 (-0.518947) | 0.288326 / 0.579283 (-0.290957) | 0.271976 / 0.434364 (-0.162388) | 0.328402 / 0.540337 (-0.211936) | 0.418102 / 1.386936 (-0.968834) |

</details>
</details>

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<details>
<summary>Show benchmarks</summary>

PyArrow==8.0.0

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.005375 / 0.011353 (-0.005978) | 0.003530 / 0.011008 (-0.007478) | 0.062521 / 0.038508 (0.024013) | 0.051514 / 0.023109 (0.028405) | 0.241623 / 0.275898 (-0.034275) | 0.269054 / 0.323480 (-0.054426) | 0.002877 / 0.007986 (-0.005109) | 0.002724 / 0.004328 (-0.001605) | 0.049045 / 0.004250 (0.044794) | 0.038560 / 0.037052 (0.001507) | 0.248437 / 0.258489 (-0.010052) | 0.276762 / 0.293841 (-0.017079) | 0.027522 / 0.128546 (-0.101024) | 0.010817 / 0.075646 (-0.064829) | 0.208686 / 0.419271 (-0.210585) | 0.035818 / 0.043533 (-0.007715) | 0.249398 / 0.255139 (-0.005741) | 0.268288 / 0.283200 (-0.014911) | 0.019039 / 0.141683 (-0.122644) | 1.135115 / 1.452155 (-0.317040) | 1.195531 / 1.492716 (-0.297185) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.093126 / 0.018006 (0.075120) | 0.301028 / 0.000490 (0.300539) | 0.000222 / 0.000200 (0.000023) | 0.000062 / 0.000054 (0.000007) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.018385 / 0.037411 (-0.019027) | 0.060902 / 0.014526 (0.046376) | 0.073168 / 0.176557 (-0.103389) | 0.119216 / 0.737135 (-0.617919) | 0.074225 / 0.296338 (-0.222114) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.283749 / 0.215209 (0.068540) | 2.741609 / 2.077655 (0.663954) | 1.483439 / 1.504120 (-0.020681) | 1.352896 / 1.541195 (-0.188299) | 1.378824 / 1.468490 (-0.089667) | 0.548731 / 4.584777 (-4.036046) | 2.342717 / 3.745712 (-1.402995) | 2.791592 / 5.269862 (-2.478269) | 1.740605 / 4.565676 (-2.825071) | 0.062059 / 0.424275 (-0.362216) | 0.005028 / 0.007607 (-0.002579) | 0.339205 / 0.226044 (0.113161) | 3.353386 / 2.268929 (1.084458) | 1.785717 / 55.444624 (-53.658907) | 1.523390 / 6.876477 (-5.353086) | 1.556999 / 2.142072 (-0.585073) | 0.636745 / 4.805227 (-4.168483) | 0.115821 / 6.500664 (-6.384843) | 0.042200 / 0.075469 (-0.033269) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.948678 / 1.841788 (-0.893110) | 11.588670 / 8.074308 (3.514362) | 10.897130 / 10.191392 (0.705738) | 0.140068 / 0.680424 (-0.540356) | 0.014565 / 0.534201 (-0.519636) | 0.286336 / 0.579283 (-0.292947) | 0.265292 / 0.434364 (-0.169072) | 0.324146 / 0.540337 (-0.216192) | 0.413463 / 1.386936 (-0.973473) |

</details>
PyArrow==latest

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.005187 / 0.011353 (-0.006165) | 0.003471 / 0.011008 (-0.007537) | 0.048968 / 0.038508 (0.010460) | 0.051285 / 0.023109 (0.028176) | 0.283286 / 0.275898 (0.007388) | 0.307046 / 0.323480 (-0.016434) | 0.004017 / 0.007986 (-0.003969) | 0.002655 / 0.004328 (-0.001673) | 0.047762 / 0.004250 (0.043512) | 0.039855 / 0.037052 (0.002803) | 0.283101 / 0.258489 (0.024612) | 0.312905 / 0.293841 (0.019064) | 0.028188 / 0.128546 (-0.100358) | 0.010849 / 0.075646 (-0.064797) | 0.058112 / 0.419271 (-0.361159) | 0.032163 / 0.043533 (-0.011369) | 0.280825 / 0.255139 (0.025686) | 0.300946 / 0.283200 (0.017747) | 0.017409 / 0.141683 (-0.124274) | 1.127360 / 1.452155 (-0.324795) | 1.180409 / 1.492716 (-0.312307) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.093186 / 0.018006 (0.075180) | 0.300827 / 0.000490 (0.300338) | 0.000220 / 0.000200 (0.000020) | 0.000052 / 0.000054 (-0.000002) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.021560 / 0.037411 (-0.015851) | 0.069158 / 0.014526 (0.054632) | 0.080953 / 0.176557 (-0.095603) | 0.119071 / 0.737135 (-0.618064) | 0.082817 / 0.296338 (-0.213521) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.307259 / 0.215209 (0.092050) | 2.996058 / 2.077655 (0.918404) | 1.627406 / 1.504120 (0.123286) | 1.500715 / 1.541195 (-0.040480) | 1.524278 / 1.468490 (0.055788) | 0.569711 / 4.584777 (-4.015066) | 2.436132 / 3.745712 (-1.309580) | 2.796995 / 5.269862 (-2.472866) | 1.760701 / 4.565676 (-2.804975) | 0.063521 / 0.424275 (-0.360754) | 0.004909 / 0.007607 (-0.002698) | 0.359129 / 0.226044 (0.133085) | 3.567278 / 2.268929 (1.298349) | 2.013821 / 55.444624 (-53.430804) | 1.708021 / 6.876477 (-5.168456) | 1.738959 / 2.142072 (-0.403114) | 0.648620 / 4.805227 (-4.156607) | 0.122016 / 6.500664 (-6.378648) | 0.041802 / 0.075469 (-0.033667) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.985208 / 1.841788 (-0.856579) | 12.307785 / 8.074308 (4.233477) | 10.587262 / 10.191392 (0.395870) | 0.130468 / 0.680424 (-0.549956) | 0.014912 / 0.534201 (-0.519289) | 0.293822 / 0.579283 (-0.285461) | 0.283021 / 0.434364 (-0.151343) | 0.329560 / 0.540337 (-0.210777) | 0.424741 / 1.386936 (-0.962195) |

</details>
</details>

![](https://cml.dev/watermark.png#04426d9c8e0aa5c97af2826064287f8cab6bece0 "CML watermark")