title: git checkout to a branch takes long time
body: <p>I am on Ubuntu 17.10 and I am using git (version 2.14.1). Whenever I create a branch from master and try to checkout to it (or to the master from it), it takes a whole lot of time, around few minutes, sometimes nearly 10 minutes. True, that I have a few GBs of data, but as far as I understand, the whole data doesn't actually get copied and instead only the changes are saved. What then could be the issue behind this? </p>