mozilla / memchaser

Firefox extension to chase the memory usage and garbage collector activity
https://wiki.mozilla.org/QA/Automation_Services/Projects/Addons/MemChaser
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Provide recourse for warning "red" values (dynamic update of threshold) #89

Open anon-user opened 12 years ago

anon-user commented 12 years ago

My minimum & nominal observed GC value is a little over .2s ==> red My maximum observed GC value is a little under .6s ==> red It's always red.

Seems this should be a graduated scale -- although .2s may still be at the high end. From the source:

const GARBAGE_COLLECTOR_DURATION_WARNING = 100; // ms

Therefore: .2s ==> twice as long as max expected .6s ==> six times as long as max expected

Maybe we just continue to set red at .1s but then also bold at .2s? Even then, it would always appear as bold red in my case.

So... we've flagged GC as being anomalous; however, what's the user's recourse? Oh... Firefox GC is not a good value ... darn?

How does a user differentiate between barely over the threshold of max expected and an order of magnitude -- well, 6x here -- vs the max expected?

How does a user determine the impact of a red value? It's red, well not performing as well as it could, I guess... but I knew it seemed slow?

We should provide means for a user to better understand what is being reported and be able to take action based on what is reported -- hopefully to improve things even if only a little...

dglol commented 12 years ago

Interesting idea. I think, whether this was intentional or not, that less than 100ms is an industry rule of thumb for the perception of being 'instant' and that lag is easier to perceive when it is greater than 100ms

whimboo commented 12 years ago

It has been set to 100ms because of this reason, correct.