When running httperf if you get this error: httperf --timeout=5 --client=0/1 --server=domU-12-31-39-00-A9-F7 --port=80 --uri=/articles.html --rate=500 --send-buffer=4096 --recv-buffer=16384 --num-conns=20000 --num-calls=10 httperf: warning: open file limit > FD_SETSIZE; limiting max. # of open files to FD_SETSIZE Maximum connect burst length: 50 Total: connections 9789 requests 96039 replies 95959