What is the optimal way for poster presentation in conference? I am presenting (PPT) my regular research paper in a computer science conference. Additionally, the conference has a poster session of 2 hr. What I find difficult in poster session is that the process of redundantly speaking the same things again and again.

E.g. If 1 person comes, I need to start. He may leave in half way. Then, next 2-3 person come, I have to restart.

What is the best way to deal with this problem? 

One solution I think is: Wait for few minutes, let a bunch of people present and then start presentation.
I strongly suggest that you don't treat it as a sequence of presentations, but more as an opportunity to meet people, exchange business cards, listen to their questions and comments and just interact with them in a normal way. 

Usually the venue is a bit chaotic so you aren't likely to be very successful with a presentation. Have several copies of your paper, or at least an abstract. Make sure you include contact information. Have an actual poster that gives a bit of an outline of what you do, but not too dense. 

Some of the people wandering by will be truly interested, others not as much. Some will be students looking for ideas and some will be professors looking for future employees if you are a student yourself. 

Keep it informal. Make a good personal impression. Let the formal presentation and the paper stand on its own. You don't really need to sell it. Of course, a few questions might be detailed and you can deal with that. 

I've been to a lot of these, both as a "presenter" and a viewer. What I want as a visitor is a quick overview from the poster and the opportunity to ask a question.