How can i increasing the speed of bagging classifier

currently, I am working on big data classification.I have tested many classifiers on some small datasets and big datasets.at the end, i have noticed that two classifiers achieved the best results but with long running time (Bagging & Random Tree). I tried creating an updateable version of both classifiers but it reduced the running time only a little bit around 10%. My question is how can I achieve a tangible saving in terms of running time for both classifiers or at least one of them.

Thanks in advance for the help.