PokerTracker

I'm importing hands from my disk and I'm already taking 48 hours with it and I still have 30 hours remaining, but the speed is constantly slowing down, can I click 'Stop Getting Hands', reset and then start loading the remaining hands?? I'm afraid to do so after so many hands were already imported, does the whole process cancel when I do so?

Clicking Stop Getting Hands does not cancel the import - the imported data will stay in your database, and if you want to import more hands you'll certainly be able to do so.

Is there any particular operation I should do after importing the whole database? what does rebuild cache actually do?

You don't need to do anything manually - the cache will be updated automatically as part of the import.
Normally the cache doesn't need to be rebuilt manually unless a problem occurs and you're experiencing slow performance, and even then it's best to contact support first. For more information on what the cache is for see this guide.

'Tune PostgreSQL' doesnt work now, I get 'Automatic tuning failed.' message and that's all.

Are things working OK other than that?
What version of PostgreSQL do you have installed? (It should say in the bottom right corner of the Database Management window.)

Postgresql 9.5.3. The HUD lags a little bit, sometimes takes 2-3 hands to even load it up, my previous database was even larger and it didnt lag this way, this one is 47gb, previous one was 55gb.

should I reinstall to 9.3 again ???

Please restart PT4 using the logging enabled link on your Start Menu, click Get Hands While Playing and play for a few hands until the HUD shows. Then report this issue via our support system with the log file - that will help us figure out what is going on here and get it fixed for you. You can find that file by clicking File --> Show User Data Folder in the main PT4 window - the file we need is the text file called PokerTracker4 that is in that folder.

Once we have your log we'll be in a much better spot to tell you exactly what's going on here and what steps to take.

If I just reinstall postgresql to 9.3 version, will I have to restore database again or just change directories and the db will open in 9.3 too?