Please add reset_data to lgb.cv

[NamLQ]

The lgb.train has the argument reset_data = T to release the data from the model as in #879. In the case of multiple k-fold cv the RAM is eaten so fast, so it would much better if lgb.cv also has the argument reset_data.

Thank you very much.

[guolinke]

@NamLQ you can call gc every time after cv, since lgb.cv don't save cv-folds objects.

[guolinke]

sorry, it seems R-package returns a CV-booster.
@Laurae2 it that possible to only returns the cv-results like in python-package: https://github.com/Microsoft/LightGBM/blob/master/python-package/lightgbm/engine.py#L501 ?

[NamLQ]

Please keep the CV-booster, because I need it to make a fold prediction. So just release the data is enough.

[guolinke]

@Laurae2 @StrikerRUS
why the cv has different behaviours (return results) in python and R package.
Should we make them the same?

[guolinke]

@NamLQ updated

[StrikerRUS]

@guolinke I've discovered LightGBM when cv had been already implemented, therefore I don't know.

Also, we have several issues about Python cv behavior enhancements: #283, #1445, #1105.