The speed of my OJS web site is very slow

I installed OJS for my web site. However, the speed is very slow. Would you please let me know what shoud I do to speed up the web site? Thanks.

My web site is : rapsy.obhrm.net, many many thanks.

Can you describe in detail what you are doing that seems to be a slow operation? Is this something we can see from the public interface?

Is the same with me, my web site is too slow on geral, i need to whait 20 seconds to load the page, what can i do to solve this?