How to quickly stress test a web server

app.sh

curl -s "http://google.com?[1-1000]"
This will make 1000 calls to google i.e.

http://google.com?1  
http://google.com?2  
http://google.com?3 
\... 
http://google.com?1000
So say you want to stress test your web application and it won't complain if it's fed an extra parameter, 10,000 calls could be done something like.

curl -s "http://yourappp.com/your_page_to_test.php?[1-10000]"
Multiple Pages
Easy just add each page to the command line.

curl -s "http://yourapp.com/page1.php?[1-1000]" "http://yourappp.com/page2.php?[1-1000]"
Or even...

curl -s "http://yourapp.com/page{1, 2}.php?[1-1000]"
Timing
Using the time command we can get a view on our performance

time curl -s "http://yourapp.com/page{1, 2}.php?[1-1000]"  

real 0m0.606s 
user 0m0.009s 
sys 0m0.008s 
Simulating consecutive users
OK, this is great for sending a whole bunch of calls one after the other but what about simultaneous calls. For this we can place the Curl calls in a script and set them running in the background. i.e. my_stress_test.sh

curl -s "http://yourapp.com/page{1, 2}.php?[1-1000]" &
pidlist="$pidlist $!" 
curl -s "http://yourapp.com/page{1, 2}.php?[1-1000]" &
pidlist="$pidlist $!" 
curl -s "http://yourapp.com/page{1, 2}.php?[1-1000]" &
pidlist="$pidlist $!" 
curl -s "http://yourapp.com/page{1, 2}.php?[1-1000]" &
pidlist="$pidlist $!" 
curl -s "http://yourapp.com/page{1, 2}.php?[1-1000]" &
pidlist="$pidlist $!" 
curl -s "http://yourapp.com/page{1, 2}.php?[1-1000]" &
pidlist="$pidlist $!" 
curl -s "http://yourapp.com/page{1, 2}.php?[1-1000]" &
pidlist="$pidlist $!"  

for job in $pidlist do 
  echo $job     
  wait $job || let "FAIL+=1" 
done  

if [ "$FAIL" == "0" ]; then 
  echo "YAY!" 
else 
  echo "FAIL! ($FAIL)" 
fi