I am facing issue of slowness, Since my database has 15lakh data now and will increase to 1crore in future.
Now If I make a search then it will take very long time to respond. My activity string also take very long time to respond. I have already done the indexing in MySQL 5.7 database.
If you need to handle such a large installation you need to adequately plan and deploy database hardware, and probably tweak some queries and have a proper data clean-up strategy in place.