Could you post a sentence or two about which particular calls you're concerned with here? We just ran across this bug in [qf] nomination bug triage, and we have no idea how to prioritize it. :) Eliminating hashtable lookups is big, though, clearly, so this is probably [qf:p1] assuming that there's something to be done here. (Alternately: maybe you've got a patch nearly ready, which will make this clearer...)
Created attachment 8876106 [details] [diff] [review] Avoid doing unnecessary hashtable lookups in ImageTracker::Add/Remove Fairly straightforward: replace Get+Put with LookupForAdd, and Get+Remove with LookupRemoveIf.
Triaging as [qf:p1], as straightforward removal of redundant hashtable lookups (known in general to be involved in QF perf issues).
Pushed by firstname.lastname@example.org: https://hg.mozilla.org/integration/mozilla-inbound/rev/46cb9923c169 Avoid doing unnecessary hashtable lookups in ImageTracker::Add/Remove. r=froydnj