Question (potential issue?) related to datasets caching
Thanks for the feedback, we'll work in improving this aspect of the documentation.

> Where are these files stored? I guess not in the temporary directory that is removed...

We're using the Arrow file format to load datasets. Therefore each time you load a dataset, it is prepared as an arrow file on your disk. By default the file is located in the ~/.cache/huggingface/datasets/<dataset_name>/<config_id>/<version> directory.

> What information is used to create the directory/filenames where the files are stored?

The config_id contains a hash that takes into account:
- the dataset loader used and its source code (e.g. the "csv" loader)
- the arguments passed to the loader (e.g. the csv delimiter)
- metadata of the local data files if any (e.g. their timestamps)

> I'm concerned about the following scenario: if I have a file, let's say train.csv at path the_path, run once, the dataset is prepared, some models are run, etc. Now let's say there is an issue and I recreate train.csv at the same path the_path. Is there enough information in the temporary name/hash to not reload the old prepared dataset (e.g., timestamp of the file)? Or is it going to reload the old prepared file?

Yes the timestamp of the local csv file is taken into account. If you edit your csv file, the config_id will change and loading the dataset will create a new arrow file.
I thought I had disabled datasets caching in my code, as follows:
```
from datasets import set_caching_enabled
...
def main():

    # disable caching in datasets
    set_caching_enabled(False)
```
However, in my log files I see messages like the following:

```
04/07/2021 18:34:42 - WARNING - datasets.builder -   Using custom data configuration default-888a87931cbc5877
04/07/2021 18:34:42 - WARNING - datasets.builder -   Reusing dataset csv (xxxx/cache-transformers/datasets/csv/default-888a87931cbc5877/0.0.0/965b6429be0fc05f975b608ce64e1fa941cc8fb4f30629b523d2390f3c0e1a93
```
Can you please let me know what this reusing dataset csv means? I wouldn't expect any reusing with the datasets caching disabled. Thank you!
Question (potential issue?) related to datasets caching 
 I thought I had disabled datasets caching in my code, as follows:
```
from datasets import set_caching_enabled
...
def main():

    # disable caching in datasets
    set_caching_enabled(False)
```
However, in my log files I see messages like the following:

```
04/07/2021 18:34:42 - WARNING - datasets.builder -   Using custom data configuration default-888a87931cbc5877
04/07/2021 18:34:42 - WARNING - datasets.builder -   Reusing dataset csv (xxxx/cache-transformers/datasets/csv/default-888a87931cbc5877/0.0.0/965b6429be0fc05f975b608ce64e1fa941cc8fb4f30629b523d2390f3c0e1a93
```
Can you please let me know what this reusing dataset csv means? I wouldn't expect any reusing with the datasets caching disabled. Thank you! 
 Thanks for the feedback, we'll work in improving this aspect of the documentation.

> Where are these files stored? I guess not in the temporary directory that is removed...

We're using the Arrow file format to load datasets. Therefore each time you load a dataset, it is prepared as an arrow file on your disk. By default the file is located in the ~/.cache/huggingface/datasets/<dataset_name>/<config_id>/<version> directory.

> What information is used to create the directory/filenames where the files are stored?

The config_id contains a hash that takes into account:
- the dataset loader used and its source code (e.g. the "csv" loader)
- the arguments passed to the loader (e.g. the csv delimiter)
- metadata of the local data files if any (e.g. their timestamps)

> I'm concerned about the following scenario: if I have a file, let's say train.csv at path the_path, run once, the dataset is prepared, some models are run, etc. Now let's say there is an issue and I recreate train.csv at the same path the_path. Is there enough information in the temporary name/hash to not reload the old prepared dataset (e.g., timestamp of the file)? Or is it going to reload the old prepared file?

Yes the timestamp of the local csv file is taken into account. If you edit your csv file, the config_id will change and loading the dataset will create a new arrow file.