Better multi-gpu example

Use Qwen1.5-0.5B-Chat as an easy example for multi-GPU

the previous example was using a model for translation and the way it was setup was not really the right way to use the model.

Comments:
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_6646). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

<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) | 0.005598 / 0.011353 (-0.005755) | 0.003640 / 0.011008 (-0.007369) | 0.064557 / 0.038508 (0.026049) | 0.029645 / 0.023109 (0.006536) | 0.243695 / 0.275898 (-0.032203) | 0.261252 / 0.323480 (-0.062228) | 0.004067 / 0.007986 (-0.003919) | 0.002883 / 0.004328 (-0.001446) | 0.049192 / 0.004250 (0.044942) | 0.045299 / 0.037052 (0.008246) | 0.273207 / 0.258489 (0.014718) | 0.288668 / 0.293841 (-0.005173) | 0.028114 / 0.128546 (-0.100432) | 0.010597 / 0.075646 (-0.065049) | 0.215345 / 0.419271 (-0.203927) | 0.036119 / 0.043533 (-0.007414) | 0.243718 / 0.255139 (-0.011421) | 0.266657 / 0.283200 (-0.016543) | 0.018176 / 0.141683 (-0.123507) | 1.127926 / 1.452155 (-0.324229) | 1.168066 / 1.492716 (-0.324650) |

### 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) | 0.096001 / 0.018006 (0.077994) | 0.304317 / 0.000490 (0.303828) | 0.000209 / 0.000200 (0.000009) | 0.000051 / 0.000054 (-0.000004) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.018241 / 0.037411 (-0.019170) | 0.061505 / 0.014526 (0.046979) | 0.072456 / 0.176557 (-0.104101) | 0.118315 / 0.737135 (-0.618821) | 0.075154 / 0.296338 (-0.221184) |

### 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) | 0.278748 / 0.215209 (0.063538) | 2.729923 / 2.077655 (0.652268) | 1.416835 / 1.504120 (-0.087285) | 1.294016 / 1.541195 (-0.247179) | 1.323249 / 1.468490 (-0.145241) | 0.575389 / 4.584777 (-4.009388) | 2.404923 / 3.745712 (-1.340789) | 2.769233 / 5.269862 (-2.500629) | 1.742340 / 4.565676 (-2.823336) | 0.062664 / 0.424275 (-0.361611) | 0.004951 / 0.007607 (-0.002656) | 0.335024 / 0.226044 (0.108979) | 3.291446 / 2.268929 (1.022518) | 1.797095 / 55.444624 (-53.647530) | 1.532963 / 6.876477 (-5.343513) | 1.529315 / 2.142072 (-0.612758) | 0.654922 / 4.805227 (-4.150305) | 0.118772 / 6.500664 (-6.381892) | 0.042034 / 0.075469 (-0.033435) |

### 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) | 0.983646 / 1.841788 (-0.858141) | 11.518625 / 8.074308 (3.444317) | 9.538781 / 10.191392 (-0.652611) | 0.140300 / 0.680424 (-0.540124) | 0.013966 / 0.534201 (-0.520235) | 0.287071 / 0.579283 (-0.292212) | 0.270201 / 0.434364 (-0.164163) | 0.323294 / 0.540337 (-0.217044) | 0.418130 / 1.386936 (-0.968806) |

</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) | 0.005508 / 0.011353 (-0.005844) | 0.003714 / 0.011008 (-0.007294) | 0.050031 / 0.038508 (0.011523) | 0.031866 / 0.023109 (0.008756) | 0.272248 / 0.275898 (-0.003650) | 0.295105 / 0.323480 (-0.028375) | 0.005179 / 0.007986 (-0.002807) | 0.002820 / 0.004328 (-0.001508) | 0.048896 / 0.004250 (0.044646) | 0.045975 / 0.037052 (0.008922) | 0.287662 / 0.258489 (0.029173) | 0.321139 / 0.293841 (0.027298) | 0.049242 / 0.128546 (-0.079304) | 0.010732 / 0.075646 (-0.064914) | 0.057943 / 0.419271 (-0.361328) | 0.033527 / 0.043533 (-0.010006) | 0.271746 / 0.255139 (0.016607) | 0.291404 / 0.283200 (0.008204) | 0.019351 / 0.141683 (-0.122332) | 1.157221 / 1.452155 (-0.294934) | 1.215757 / 1.492716 (-0.276959) |

### 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) | 0.096950 / 0.018006 (0.078944) | 0.312002 / 0.000490 (0.311512) | 0.000223 / 0.000200 (0.000023) | 0.000055 / 0.000054 (0.000001) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.022288 / 0.037411 (-0.015123) | 0.075282 / 0.014526 (0.060756) | 0.087445 / 0.176557 (-0.089112) | 0.125617 / 0.737135 (-0.611519) | 0.088878 / 0.296338 (-0.207460) |

### 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) | 0.291961 / 0.215209 (0.076752) | 2.881445 / 2.077655 (0.803790) | 1.586128 / 1.504120 (0.082008) | 1.458636 / 1.541195 (-0.082558) | 1.487001 / 1.468490 (0.018511) | 0.575466 / 4.584777 (-4.009311) | 2.454941 / 3.745712 (-1.290771) | 2.878077 / 5.269862 (-2.391785) | 1.787215 / 4.565676 (-2.778462) | 0.064010 / 0.424275 (-0.360265) | 0.005092 / 0.007607 (-0.002516) | 0.360500 / 0.226044 (0.134455) | 3.465574 / 2.268929 (1.196646) | 1.957516 / 55.444624 (-53.487108) | 1.666282 / 6.876477 (-5.210195) | 1.690070 / 2.142072 (-0.452002) | 0.661323 / 4.805227 (-4.143905) | 0.117824 / 6.500664 (-6.382840) | 0.042286 / 0.075469 (-0.033183) |

### 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) | 1.026517 / 1.841788 (-0.815270) | 12.083347 / 8.074308 (4.009039) | 10.269319 / 10.191392 (0.077927) | 0.139253 / 0.680424 (-0.541171) | 0.016258 / 0.534201 (-0.517943) | 0.290583 / 0.579283 (-0.288700) | 0.284338 / 0.434364 (-0.150026) | 0.335865 / 0.540337 (-0.204473) | 0.416600 / 1.386936 (-0.970336) |

</details>
</details>

![](https://cml.dev/watermark.png#ba3cfad91e9366cda0ba203700fc745d8bcd1f17 "CML watermark")


Thanks, I was needing this example today <3