Xgboost Parameter Tuning
Typically XGBoost does not require many parameters to be tuned to get good performances. 

I would start with optimizing the n_estimators, max_depth and min_child_weight parameters only. This should already bring you close enough.

Another thing you can do to speed-up the process is to prefer Random Search over Grid Search, since in most cases is as or more effective.

You could also have a look at the LightGBM implementation, which is faster (and needs less memory) than XGBoost.