Bytes In Varying

[tristandunn]

I've noticed Bytes In can vary between tests, even when the content is the same size. I've witnessed this on the public version and a private install. I take it this is due to measuring the raw traffic versus just the file contents. Is that correct?

Here's a simple example of small variations, which I've been able to reproduce on most sites:

• http://www.webpagetest.org/result/110617_MS_VN3E/
• http://www.webpagetest.org/result/110617_PM_VN3F/
  

I've also seen fairly large variations on my 2.2 private install, but it's also between two different branches of code. Although my changes are at most about a 30kb difference in total, I have seen WPT report up to 100kb difference in total. This is worrisome as it makes it harder to trust the results. I don't have the exported information with me, but will definitely post it soon if it's needed. Any ideas what could be causing this?