Here's the metrics we're looking for with CSS Grid. We want this to look like a funnel where the number of Firefox Developers who have seen an element with `display: grid` CSS is our total addressable market. How many CSS Grid elements DevTools sees How many times the Layout panel is opened How many of the Grid layout views are activated What CSS Grid Layout options are turned on

You will find that I removed the "navigate" event listener on the layout actor for the tab actor. I found that this "navigate" event actually fires off 4 times per navigation compare to the tab target on the client side. It's actually kinda crazy. I am using scalarAdd instead of toolOpened because I found that toolOpened only sets the scalar value to 1, which seems to be very wrong instead of incrementally adding the count. I am gonna have follow up patches that will make sure we don't count on reload, but that has been a bit tricky since the "will-navigate" event will give you the url of the page that you are navigating to, so, not actually possible to easily save the previous URL before navigation. The metric information that I posted on comment 1 was actually written by clarkbw.

Requesting data vouches from clarkbw

Comment on attachment 8879017 [details] Bug 1373483 - Part 1: Add telemetry for the grid inspector. https://reviewboard.mozilla.org/r/150298/#review154964 Looks good to me, but I'd like Mike to chime in on that too.

Comment on attachment 8879017 [details] Bug 1373483 - Part 1: Add telemetry for the grid inspector. https://reviewboard.mozilla.org/r/150298/#review155000 Looks good to me.

(In reply to Gabriel [:gl] (ΦωΦ) from comment #4) > Requesting data vouches from clarkbw Yes, I'll be tracking this data on redash to better understand ways to optimize the interface for grid users as well as developing communication strategies to better inform people how to use the tools.

Comment on attachment 8879017 [details] Bug 1373483 - Part 1: Add telemetry for the grid inspector. https://reviewboard.mozilla.org/r/150298/#review155286 ::: toolkit/components/telemetry/Histograms.json:10085 (Diff revision 1) > "description": "Reports the command name used in GCLI e.g. 'screenshot'" > }, > + "DEVTOOLS_NUMBER_OF_CSS_GRIDS_IN_A_PAGE": { > + "record_in_processes": ["main", "content"], > + "alert_emails": ["dev-developer-tools@lists.mozilla.org"], > + "expires_in_version": "never", The usual rule is that a permanent histogram should have an automated test, because it's not uncommon for code refactorings to silently break telemetry metrics. I don't see any automated tests in this changeset. Is there a reason why this value is not testable? ::: toolkit/components/telemetry/Histograms.json:10086 (Diff revision 1) > }, > + "DEVTOOLS_NUMBER_OF_CSS_GRIDS_IN_A_PAGE": { > + "record_in_processes": ["main", "content"], > + "alert_emails": ["dev-developer-tools@lists.mozilla.org"], > + "expires_in_version": "never", > + "kind": "enumerated", I don't understand using an enumerated histogram for this. If this is a counter value it should be a linear or exponential histogram rather than enumerated. An enumerated histogram should warn if you record a value outside of boundaries, while a linear/exponential histogram won't. ::: toolkit/components/telemetry/Histograms.json:10089 (Diff revision 1) > + "alert_emails": ["dev-developer-tools@lists.mozilla.org"], > + "expires_in_version": "never", > + "kind": "enumerated", > + "n_values": 25, > + "bug_numbers": [1373483], > + "description": "How many CSS Grid elements DevTools sees?", Please improve this description. A metric description should include both *what* is measured and *when* it is measured. I don't know the details of this one, but perhaps: "On page load when the devtools are open, record how many grid elements are present in the page."

Comment on attachment 8879663 [details] [diff] [review] 1373483.patch [1.0] Notes copied from IRC: * don't add this to histogram-whitelists: that's intended for old histograms which don't follow the guidelines, and new ones should hardly ever be added to that list * I'm pretty certain you want n_buckets to be 32: that gives you one bucket for <0, 30 buckets for 0-29, and one bucket for 30+ data-r=me with those nits fixed

Pushed by gabriel.luong@gmail.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/830b3b513bf1 Add telemetry for the grid inspector. r=pbro. data-r=bsmedberg

Backed out for build failures like https://treeherder.mozilla.org/logviewer.html#?job_id=108671626&repo=mozilla-inbound https://hg.mozilla.org/integration/mozilla-inbound/rev/32adb4bf3e162ee33cc685d9b2028286768c3df0

Pushed by gabriel.luong@gmail.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/86f86f971014 Add telemetry for the grid inspector. r=pbro. data-r=bsmedberg