I want simulate load on site, (site is write on php). for example I want simulate simultaneous 10 000 request on same page (for example index.php), after search I found "jmeter" (but I still not test it). Other, what program you can recommend for this?
Use Apache Bench. It is a command line load tester. If you want to test 10,000 simultaneous users use this command line :
ab -c 10000 http://www.mysite.com/
-c is the number of concurrent requests..
ApacheBench is great for this sort of thing, and is probably already installed on your machine.