add gs

RCCService2018/content/LuaPackages/RoactImpl/Instrumentation.lua

@@ -0,0 +1,104 @@
+--[[
+	An optional instrumentation layer that the reconciler calls into to record
+	various events.
+
+	Tracks a number of stats, including:
+		Recorded stats:
+		- Render count by component
+		- Update request count by component
+		- Actual update count by component
+		- shouldUpdate returned true count by component
+		- Time taken to run shouldUpdate
+		- Time taken to render by component
+		Derivable stats (for profiling manually or with a future tool):
+		- Average render time by component
+		- Percent of total render time by component
+		- Percent of time shouldUpdate returns true
+		- Average shouldUpdate time by component
+		- Percent of total shouldUpdate time by component
+]]
+
+local Instrumentation = {}
+
+local componentStats = {}
+
+--[[
+	Determines name of component from the given instance handle and returns a
+	stat object from the componentStats table, generating a new one if needed
+]]
+local function getStatEntry(handle)
+	local name
+	if handle and handle._element and handle._element.component then
+		name = tostring(handle._element.component)
+	else
+		warn("Component name not valid for " .. tostring(handle._key))
+		return nil
+	end
+	local entry = componentStats[name]
+	if not entry then
+		entry = {
+			-- update requests
+			updateReqCount = 0,
+			-- actual updates
+			didUpdateCount = 0,
+			-- time spent in shouldUpdate
+			shouldUpdateTime = 0,
+			-- number of renders
+			renderCount = 0,
+			-- total render time spent
+			renderTime = 0,
+		}
+		componentStats[name] = entry
+	end
+
+	return entry
+end
+
+--[[
+	Logs the time taken and resulting value of a Component's shouldUpdate function
+]]
+function Instrumentation.logShouldUpdate(handle, updateNeeded, shouldUpdateTime)
+	-- Grab or create associated entry in stats table
+	local statEntry = getStatEntry(handle)
+	if statEntry then
+		-- Increment the total number of times update was invoked
+		statEntry.updateReqCount = statEntry.updateReqCount + 1
+
+		-- Increment (when applicable) total number of times shouldUpdate returned true
+		statEntry.didUpdateCount = statEntry.didUpdateCount + (updateNeeded and 1 or 0)
+
+		-- Add time spent checking if an update is needed (in millis) to total time
+		statEntry.shouldUpdateTime = statEntry.shouldUpdateTime + shouldUpdateTime * 1000
+	end
+end
+
+--[[
+	Logs the time taken value of a Component's render function
+]]
+function Instrumentation.logRenderTime(handle, renderTime)
+	-- Grab or create associated entry in stats table
+	local statEntry = getStatEntry(handle)
+	if statEntry then
+		-- Increment total render count
+		statEntry.renderCount = statEntry.renderCount + 1
+
+		-- Add render time (in millis) to total rendering time
+		statEntry.renderTime = statEntry.renderTime + renderTime * 1000
+	end
+end
+
+--[[
+	Clears all the stats collected thus far. Useful for testing and for profiling in the future
+]]
+function Instrumentation.clearCollectedStats()
+	componentStats = {}
+end
+
+--[[
+	Returns all the stats collected thus far. Useful for testing and for profiling in the future
+]]
+function Instrumentation.getCollectedStats()
+	return componentStats
+end
+
+return Instrumentation