Hello Chethan,

As per my knowledge grid shouldn't take 2-3 sec to highlight the row , so i am more curios to know what you are doing in your project causing this. Are you using any event like BeforeRowActivate,or BeforeCellActivate and doing something there , like looping through the rows or something ? if so then its expected.

If not then try to isolate your project and try to find what is causing it and share that information with us for further investigation .

or you can also share your sample with us to test and investigate the issue.