585777 - Measure Disk Cache Utilization

Status: RESOLVED INCOMPLETE

(Core :: Networking: Cache, defect)

Description

[Byron Milligan [:byronm]]

Attachment: xpcshell test to measure disk cache hit rate and eviction statistics.

We know that we want to improve the utilization of our disk cache. There are a lot of ideas as to how to go about this, but in order to have a good starting point, and a means of checking if we are actually improving things, we need a consistent way to test the cache.

I've written an xpcshell test which attempts to do this. The test takes as input a file of URL's. It then requests each URL in the file, and reports cache statistics, including the hit rate, the ideal hit rate (in the case where we never had to evict anything), and eviction statistics. There are probably a lot of other useful data points that we could push into this test, and I am happy to do so if anyone has suggestions.

Comment 1

[Byron Milligan [:byronm]]

Sorry everyone. I filed this a while ago but forgot to cc. This test still has some issues I need to work out; I don't fully trust it yet. (The issues are with xpcshell's non-existent profile directory, and also with the cache directory... I hope to return to this soon).

Jason, I am not sure if you would want this to be combined with the stress test suggested in Bug 588521 or if it should be kept separate. 

If anyone does look through this, please feel free to provide me with feedback. Thank you!