I use a Huawei p9 with Android 6. I notice a big problem. When I connect the phone with a Lubuntu pc trying to share files, I get e.g. that for copying 7 folders - each containing several small files for constructing html's pages - from pc to phone they are required about 10 minutes, when the total size of the folders is just 30MB!
On the other hand, when I perform the same action e.g. using instead 3 multimedia files of the same total size (i.e. 30MB), the amount of time is just 1 second (as indeed I expect).
Can someone explain why do I verify such an exaggerate discrepancy in time between the two mentioned cases? I think it may depend on the Android system (potentially by the emui p9 redesign -- otherwise every Android 6 device should have this problem!).
I finally notice that with a more dated device mounting Android 4.2, I don't encounter that inconvenience.