Mod profiling support

Config settings:
profiling = true/false (gather statistics)
detailed_profiling = true/false (break mod times to callbacks)

Chat commands:
save_mod_profile saves current statistics in debug.txt and shows on console (on default loglevel)

7 files changed, 391 insertions, 0 deletions

diff --git a/builtin/game/chatcommands.lua b/builtin/game/chatcommands.lua
index 39425f0eb..9293e98f4 100644
--- a/builtin/game/chatcommands.lua
+++ b/builtin/game/chatcommands.lua
@@ -13,6 +13,19 @@ function core.register_chatcommand(cmd, def)
 	core.chatcommands[cmd] = def
 end
 
+if core.setting_getbool("mod_profiling") then
+	local tracefct = profiling_print_log
+	profiling_print_log = nil
+	core.register_chatcommand("save_mod_profile",
+			{
+				params      = "",
+				description = "save mod profiling data to logfile " ..
+						"(depends on default loglevel)",
+				func        = tracefct,
+				privs       = { server=true }
+			})
+end
+
 core.register_on_chat_message(function(name, message)
 	local cmd, param = string.match(message, "^/([^ ]+) *(.*)")
 	if not param then
diff --git a/builtin/game/init.lua b/builtin/game/init.lua
index b878a2664..3f82f85c7 100644
--- a/builtin/game/init.lua
+++ b/builtin/game/init.lua
@@ -7,6 +7,11 @@ dofile(commonpath.."vector.lua")
 
 dofile(gamepath.."item.lua")
 dofile(gamepath.."register.lua")
+
+if core.setting_getbool("mod_profiling") then
+	dofile(gamepath.."mod_profiling.lua")
+end
+
 dofile(gamepath.."item_entity.lua")
 dofile(gamepath.."deprecated.lua")
 dofile(gamepath.."misc.lua")
diff --git a/builtin/game/mod_profiling.lua b/builtin/game/mod_profiling.lua
new file mode 100644
index 000000000..0fe99e725
--- /dev/null
+++ b/builtin/game/mod_profiling.lua
@@ -0,0 +1,355 @@
+-- Minetest: builtin/game/mod_profiling.lua
+
+local mod_statistics = {}
+mod_statistics.step_total = 0
+mod_statistics.data = {}
+mod_statistics.stats = {}
+mod_statistics.stats["total"] = {
+	min_us = math.huge,
+	max_us = 0,
+	avg_us = 0,
+	min_per = 100,
+	max_per = 100,
+	avg_per = 100
+}
+
+local replacement_table = {
+	"register_globalstep",
+	"register_on_placenode",
+	"register_on_dignode",
+	"register_on_punchnode",
+	"register_on_generated",
+	"register_on_newplayer",
+	"register_on_dieplayer",
+	"register_on_respawnplayer",
+	"register_on_prejoinplayer",
+	"register_on_joinplayer",
+	"register_on_leaveplayer",
+	"register_on_cheat",
+	"register_on_chat_message",
+	"register_on_player_receive_fields",
+	"register_on_mapgen_init",
+	"register_on_craft",
+	"register_craft_predict",
+	"register_on_item_eat"
+}
+
+--------------------------------------------------------------------------------
+function mod_statistics.log_time(type, modname, time_in_us)
+
+	if modname == nil then
+		modname = "builtin"
+	end
+	
+	if mod_statistics.data[modname] == nil then
+		mod_statistics.data[modname] = {}
+	end
+	
+	if mod_statistics.data[modname][type] == nil then
+		mod_statistics.data[modname][type] = 0
+	end
+	
+	mod_statistics.data[modname][type] =
+		mod_statistics.data[modname][type] + time_in_us
+	mod_statistics.step_total = mod_statistics.step_total + time_in_us
+end
+
+--------------------------------------------------------------------------------
+function mod_statistics.update_statistics(dtime)
+	for modname,types in pairs(mod_statistics.data) do
+		
+		if mod_statistics.stats[modname] == nil then
+			mod_statistics.stats[modname] = {
+				min_us = math.huge,
+				max_us = 0,
+				avg_us = 0,
+				min_per = 100,
+				max_per = 0,
+				avg_per = 0
+			}
+		end
+		
+		local modtime = 0
+		for type,time in pairs(types) do
+			modtime = modtime + time
+			if mod_statistics.stats[modname].types == nil then
+				mod_statistics.stats[modname].types = {}
+			end
+			if mod_statistics.stats[modname].types[type] == nil then
+				mod_statistics.stats[modname].types[type] = {
+					min_us = math.huge,
+					max_us = 0,
+					avg_us = 0,
+					min_per = 100,
+					max_per = 0,
+					avg_per = 0
+				}
+			end
+			
+			local toupdate = mod_statistics.stats[modname].types[type]
+			
+			--update us values
+			toupdate.min_us = math.min(time, toupdate.min_us)
+			toupdate.max_us = math.max(time, toupdate.max_us)
+			--TODO find better algorithm
+			toupdate.avg_us = toupdate.avg_us * 0.99 + modtime * 0.01
+				
+			--update percentage values
+			local cur_per = (time/mod_statistics.step_total) * 100
+			toupdate.min_per = math.min(toupdate.min_per, cur_per)
+				
+			toupdate.max_per = math.max(toupdate.max_per, cur_per)
+				
+			--TODO find better algorithm
+			toupdate.avg_per = toupdate.avg_per * 0.99 + cur_per * 0.01
+			
+			mod_statistics.data[modname][type] = 0
+		end
+		
+		--per mod statistics
+		--update us values
+		mod_statistics.stats[modname].min_us =
+			math.min(modtime, mod_statistics.stats[modname].min_us)
+		mod_statistics.stats[modname].max_us =
+			math.max(modtime, mod_statistics.stats[modname].max_us)
+		--TODO find better algorithm
+		mod_statistics.stats[modname].avg_us =
+			mod_statistics.stats[modname].avg_us * 0.99 + modtime * 0.01
+			
+		--update percentage values
+		local cur_per = (modtime/mod_statistics.step_total) * 100
+		mod_statistics.stats[modname].min_per =
+			math.min(mod_statistics.stats[modname].min_per, cur_per)
+			
+		mod_statistics.stats[modname].max_per =
+			math.max(mod_statistics.stats[modname].max_per, cur_per)
+			
+		--TODO find better algorithm
+		mod_statistics.stats[modname].avg_per =
+			mod_statistics.stats[modname].avg_per * 0.99 + cur_per * 0.01
+	end
+	
+	--update "total"
+	mod_statistics.stats["total"].min_us =
+		math.min(mod_statistics.step_total, mod_statistics.stats["total"].min_us)
+	mod_statistics.stats["total"].max_us =
+		math.max(mod_statistics.step_total, mod_statistics.stats["total"].max_us)
+	--TODO find better algorithm
+	mod_statistics.stats["total"].avg_us =
+		mod_statistics.stats["total"].avg_us * 0.99 +
+		mod_statistics.step_total * 0.01
+	
+	mod_statistics.step_total = 0
+end
+
+--------------------------------------------------------------------------------
+local function build_callback(log_id, fct)
+	return function( toregister )
+		local modname = core.get_current_modname()
+		
+		fct(function(...)
+			local starttime = core.get_us_time()
+			-- note maximum 10 return values are supported unless someone finds
+			-- a way to store a variable lenght return value list
+			local r0, r1, r2, r3, r4, r5, r6, r7, r8, r9 = toregister(...)
+			local delta = core.get_us_time() - starttime
+			mod_statistics.log_time(log_id, modname, delta)
+			return r0, r1, r2, r3, r4, r5, r6, r7, r8, r9
+			end
+		)
+	end
+end
+
+--------------------------------------------------------------------------------
+function profiling_print_log(cmd, filter)
+
+	print("Filter:" .. dump(filter))
+
+	core.log("action", "Values below show times/percentages per server step.")
+	core.log("action", "Following suffixes are used for entities:")
+	core.log("action", "\t#oa := on_activate, #os := on_step, #op := on_punch, #or := on_rightclick, #gs := get_staticdata")
+	core.log("action",
+		string.format("%16s | %25s | %10s | %10s | %10s | %9s | %9s | %9s",
+		"modname", "type" , "min µs", "max µs", "avg µs", "min %", "max %", "avg %")
+	)
+	core.log("action",
+		"-----------------+---------------------------+-----------+" ..
+		"-----------+-----------+-----------+-----------+-----------")
+	for modname,statistics in pairs(mod_statistics.stats) do
+		if modname ~= "total" then
+		
+			if (filter == "") or (modname == filter) then
+				if modname:len() > 16 then
+					modname = "..." .. modname:sub(-13)
+				end
+			
+				core.log("action",
+					string.format("%16s | %25s | %9d | %9d | %9d | %9d | %9d | %9d",
+					modname,
+					" ",
+					statistics.min_us,
+					statistics.max_us,
+					statistics.avg_us,
+					statistics.min_per,
+					statistics.max_per,
+					statistics.avg_per)
+				)
+				if core.setting_getbool("detailed_profiling") then
+					if statistics.types ~= nil then
+						for type,typestats in pairs(statistics.types) do
+						
+							if type:len() > 25 then
+								type = "..." .. type:sub(-22)
+							end
+						
+							core.log("action",
+								string.format(
+								"%16s | %25s | %9d | %9d | %9d | %9d | %9d | %9d",
+								" ",
+								type,
+								typestats.min_us,
+								typestats.max_us,
+								typestats.avg_us,
+								typestats.min_per,
+								typestats.max_per,
+								typestats.avg_per)
+							)
+						end
+					end
+				end
+			end
+		end
+	end
+		core.log("action",
+			"-----------------+---------------------------+-----------+" ..
+			"-----------+-----------+-----------+-----------+-----------")
+			
+	if filter == "" then
+		core.log("action",
+			string.format("%16s | %25s | %9d | %9d | %9d | %9d | %9d | %9d",
+			"total",
+			" ",
+			mod_statistics.stats["total"].min_us,
+			mod_statistics.stats["total"].max_us,
+			mod_statistics.stats["total"].avg_us,
+			mod_statistics.stats["total"].min_per,
+			mod_statistics.stats["total"].max_per,
+			mod_statistics.stats["total"].avg_per)
+		)
+	end
+	core.log("action", " ")
+	
+	return true
+end
+
+--------------------------------------------------------------------------------
+local function initialize_profiling()
+	core.log("action", "Initialize tracing")
+	
+	mod_statistics.entity_callbacks = {}
+	
+	-- first register our own globalstep handler
+	core.register_globalstep(mod_statistics.update_statistics)
+	
+	local rp_register_entity = core.register_entity
+	core.register_entity = function(name, prototype)
+		local modname = core.get_current_modname()
+		local new_on_activate = nil
+		local new_on_step = nil
+		local new_on_punch = nil
+		local new_rightclick = nil
+		local new_get_staticdata = nil
+		
+		if prototype.on_activate ~= nil then
+			local cbid = name .. "#oa"
+			mod_statistics.entity_callbacks[cbid] = prototype.on_activate
+			new_on_activate = function(self, staticdata, dtime_s)
+				local starttime = core.get_us_time()
+				mod_statistics.entity_callbacks[cbid](self, staticdata, dtime_s)
+				local delta = core.get_us_time() -starttime
+				mod_statistics.log_time(cbid, modname, delta)
+			end
+		end
+		
+		if prototype.on_step ~= nil then
+			local cbid = name .. "#os"
+			mod_statistics.entity_callbacks[cbid] = prototype.on_step
+			new_on_step = function(self, dtime)
+				local starttime = core.get_us_time()
+				mod_statistics.entity_callbacks[cbid](self, dtime)
+				local delta = core.get_us_time() -starttime
+				mod_statistics.log_time(cbid, modname, delta)
+			end
+		end
+	
+		if prototype.on_punch ~= nil then
+			local cbid = name .. "#op"
+			mod_statistics.entity_callbacks[cbid] = prototype.on_punch
+			new_on_punch = function(self, hitter)
+				local starttime = core.get_us_time()
+				mod_statistics.entity_callbacks[cbid](self, hitter)
+				local delta = core.get_us_time() -starttime
+				mod_statistics.log_time(cbid, modname, delta)
+			end
+		end
+		
+		if prototype.rightclick ~= nil then
+			local cbid = name .. "#rc"
+			mod_statistics.entity_callbacks[cbid] = prototype.rightclick
+			new_rightclick = function(self, clicker)
+				local starttime = core.get_us_time()
+				mod_statistics.entity_callbacks[cbid](self, clicker)
+				local delta = core.get_us_time() -starttime
+				mod_statistics.log_time(cbid, modname, delta)
+			end
+		end
+		
+		if prototype.get_staticdata ~= nil then
+			local cbid = name .. "#gs"
+			mod_statistics.entity_callbacks[cbid] = prototype.get_staticdata
+			new_get_staticdata = function(self)
+				local starttime = core.get_us_time()
+				mod_statistics.entity_callbacks[cbid](self)
+				local delta = core.get_us_time() -starttime
+				mod_statistics.log_time(cbid, modname, delta)
+			end
+		end
+	
+		prototype.on_activate = new_on_activate
+		prototype.on_step = new_on_step
+		prototype.on_punch = new_on_punch
+		prototype.rightclick = new_rightclick
+		prototype.get_staticdata = new_get_staticdata
+		
+		rp_register_entity(name,prototype)
+	end
+	
+	for i,v in ipairs(replacement_table) do
+		local to_replace = core[v]
+		core[v] = build_callback(v, to_replace)
+	end
+	
+	local rp_register_abm = core.register_abm
+	core.register_abm = function(spec)
+	
+		local modname = core.get_current_modname()
+	
+		local replacement_spec = {
+			nodenames = spec.nodenames,
+			neighbors = spec.neighbors,
+			interval  = spec.interval,
+			chance    = spec.chance,
+			action = function(pos, node, active_object_count, active_object_count_wider)
+				local starttime = core.get_us_time()
+				spec.action(pos, node, active_object_count, active_object_count_wider)
+				local delta = core.get_us_time() - starttime
+				mod_statistics.log_time("abm", modname, delta)
+			end
+		}
+		rp_register_abm(replacement_spec)
+	end
+	
+	core.log("action", "Mod profiling initialized")
+end
+
+initialize_profiling()
diff --git a/doc/lua_api.txt b/doc/lua_api.txt
index 3d8038f87..e027fe11d 100644
--- a/doc/lua_api.txt
+++ b/doc/lua_api.txt
@@ -1535,6 +1535,8 @@ minetest.set_node_level(pos, level)
 ^ set level of leveled node, default level = 1, if totallevel > maxlevel returns rest (total-max).
 minetest.add_node_level(pos, level)
 ^ increase level of leveled node by level, default level = 1, if totallevel > maxlevel returns rest (total-max). can be negative for decreasing
+minetest.get_time_us()
+^ get time in microseconds
 
 Inventory:
 minetest.get_inventory(location) -> InvRef
diff --git a/minetest.conf.example b/minetest.conf.example
index 24724ce28..78f51a517 100644
--- a/minetest.conf.example
+++ b/minetest.conf.example
@@ -306,6 +306,11 @@
 #    "error"  = abort on usage of deprecated call (suggested for mod developers)
 #deprecated_lua_api_handling = legacy
 
+# Mod profiler
+#mod_profiling = false
+# Detailed mod profile data
+#detailed_profiling = false
+
 # Profiler data print interval. #0 = disable.
 #profiler_print_interval = 0
 #enable_mapgen_debug_info = false
diff --git a/src/script/lua_api/l_env.cpp b/src/script/lua_api/l_env.cpp
index 42bfc4beb..e6ca846d8 100644
--- a/src/script/lua_api/l_env.cpp
+++ b/src/script/lua_api/l_env.cpp
@@ -797,6 +797,13 @@ int ModApiEnvMod::l_forceload_free_block(lua_State *L)
 	return 0;
 }
 
+// get_us_time()
+int ModApiEnvMod::l_get_us_time(lua_State *L)
+{
+	lua_pushnumber(L, porting::getTimeUs());
+	return 1;
+}
+
 void ModApiEnvMod::Initialize(lua_State *L, int top)
 {
 	API_FCT(set_node);
@@ -834,4 +841,5 @@ void ModApiEnvMod::Initialize(lua_State *L, int top)
 	API_FCT(transforming_liquid_add);
 	API_FCT(forceload_block);
 	API_FCT(forceload_free_block);
+	API_FCT(get_us_time);
 }
diff --git a/src/script/lua_api/l_env.h b/src/script/lua_api/l_env.h
index 420866d5d..76c6594ab 100644
--- a/src/script/lua_api/l_env.h
+++ b/src/script/lua_api/l_env.h
@@ -156,6 +156,9 @@ private:
 	// stops forceloading a position
 	static int l_forceload_free_block(lua_State *L);
 	
+	// get us precision time
+	static int l_get_us_time(lua_State *L);
+
 public:
 	static void Initialize(lua_State *L, int top);
 };