RedLine is great for running long duration tests. In addition to being incredibly cheap, it is also easy. We give you two ways to set long duration tests.

You can do the simple ping test by setting the # of Iterations parameter as seen in this example:

The above test 100 users will randomly ping the URL between 0 and 20 seconds (20,000 milliseconds) – so about 5 requests per second. We have set the iterations to be 3,000 – so this pattern will repeat 3,000 times. So the test will run for up to 20 seconds * 3,000 = 60,000 seconds, or about 16.7 hours.

You can also do this in your Custom Test Script. Put a loop inside of startTest around loadPage.  So something like:
$startTime = time();

do
{
  $this->loadPage();
  $duration = time() - $startTime;

  // Set progress
  recordProgress ($testNum, $duration/864);
} while ($duration < 86400);
In loadPage, you can change usleep(rand(…)) to change the delay and you can call goToUrl multiple times if you want to load multiple pages with each loop.

You can see more on writing Custom Tests here – https://www.redline13.com/blog/writing-a-custom-load-test/