Managing large recordset and maintaining database (MySQL)

Hi,

Need some help about databases. I'm currently using MySQL as my database and CI as my framework. I created a web page where I can upload a CSV file and insert them to my table. I have CSV file with 90K+ lines in it.

After the upload and insert process, and checking the dashboard of my app, it became slow. My app took around 5 seconds load time.

How can I manage large database without stalling or slowing the application? Is there any special technique on database or source code?

Thank you.

By the way, I use DataTables + Ajax to display records.