c# - Why Thread.Sleep() is so CPU intensive? -

i have asp.net page pseduo code:

while (read) {    response.outputstream.write(buffer, 0, buffer.length);    response.flush(); } 

any client requests page start download binary file. ok @ point clients had no limit in download speed changed above code this:

while (read) {    response.outputstream.write(buffer, 0, buffer.length);    response.flush();    thread.sleep(500); } 

speed problem solved now, under test 100 concurrent clients connect 1 after (3 seconds lag between each new connection) cpu usage increases when number of clients increases , when there 70 ~ 80 concurrent clients cpu reaches 100% , new connection refused. numbers may different on other machines question why thread.sleep() cpu intensive , there way speed done client without cpu rising ?

i can @ iis level need more control inside of application.

just guess:

i don't think it's thread.sleep() that's tying cpu - it's fact you're causing threads tied responding request long, , system needs spin new threads (and other resources) respond new requests since sleeping threads no longer available in thread pool.