Since the last update (0.92.2) the History and Logbook take up to 3 minutes to load, where it used to be more or less instant. I have the recorder set to store 5 days of history and purge daily.
Running on the Latest Pi 3, Class 10 SD card 12% used, never runs at more than 3% CPU day-to-day, Memory 25% CPU hits around 30% when trying to retrieve logs.
I find it painfully slow also. Unfortunately the default settings seem to log everything unless you specify restrictions.
Maybe this default behaviour is incorrect for most installations given that even with only minimal entities and automations, this bogs down and makes log and histroy pages virtually unusable after only a few days use.