+++ This bug was initially created as a clone of Bug #686948 +++
We want to collect telemetry for the following bits of information (for each of memory/disk/offline cache in this case):
Cache hit (without revalidation from the server)
Successful revalidation (hit with network overhead)
Failed revalidation (we have an entry but after asking the server it can no longer be used)
Cache miss (no entry in the cache)
To clarify, do we want something like:
-HISTOGRAM(HTTP_CACHE_DISPOSITION, 1, 5, 5, LINEAR, "HTTP Cache Hit, Reval, Failed-Reval, Miss")
+HISTOGRAM(HTTP_DISK_CACHE_DISPOSITION, 1, 5, 5, LINEAR, "HTTP Cache Hit, Reval, Failed-Reval, Miss")
+HISTOGRAM(HTTP_MEMORY_CACHE_DISPOSITION, 1, 5, 5, LINEAR, "HTTP Cache Hit, Reval, Failed-Reval, Miss")
+HISTOGRAM(HTTP_OFFLINE_CACHE_DISPOSITION, 1, 5, 5, LINEAR, "HTTP Cache Hit, Reval, Failed-Reval, Miss")
My intention was to keep the original HTTP_CACHE_DISPOSITION telemetry, and add in the other 3.
I was actually working on this one this morning (don't know why I hadn't assigned it to myself, but you doing it is fine) and got to thinking that having a "pure miss" count by device type may not work anyway (since we wouldn't have a cache entry to figure out what cache device to mark), unless we wanted to count it as a miss on all device types (which while technically correct, may end up skewing our view of things). So perhaps we should just do hit/reval/failed-reval for the device-specific bins? I'm open to suggestions.
Reassigning after discussion w/Geoff
Created attachment 563834 [details] [diff] [review]
Extends the work we already did for general disposition, and adds device-specific counts.
It seems to me as if try is fine (still new at figuring this all out...)