cache effectiveness testing

Hi,
As part of the Snappy effort, we asked QA to compare cache effectiveness 
of Firefox against Opera (which some people claim has a superior cache). 
We have some preliminary data now.


The testplan is described at 
https://wiki.mozilla.org/Performance/Snappy/Testing:BFCache_Sprint#Reference_Test_Case

I put up a snapshot of the results at 
http://people.mozilla.com/~tglek/snappy/cache1.html

I was suspecting that our cache hit-rates may be worse, but the data 
proved that theory wrong.

Data indicates that either writing to our cache is expensive or we are 
not http-pipelining/etc properly. My theory is that disk cache is to 
blame, so I asked QA to rerun this comparing to Firefox to Firefox with 
disk cache disabled.

There is also something horrible going on with huffingtonpost.

Taras