title: Firefox Race Cache With Network (RCWN) - cache can lose even when network requests are taking multiple seconds
body: <p>One of the web servers I use is excessively loaded quite often at present. This is providing some fun insights into things that it should and shouldn't be doing. However, it's also throwing up some absolutely weird behaviour on the client side as well (weird from my point of view at least).</p>
  <p>The latest gem is that the (slightly obnoxious to web servers) Firefox feature that is RCWN is kicking in even when the connection to the server is hellishly slow, and quite incredibly the cache is often losing the race for assets of under 50 kB even though the network requests for those assets have taken 2 - 4 <em>seconds</em> to come back. It's like the cache didn't even try?!</p>
  <p>This is on an i7 machine with 32 GB of RAM and no spinning rust at all (system disk = SATA SSD). To put it mildly, I'm baffled. Grateful for any insights on offer...</p>