diff --git a/df_caverns/lava_sea.lua b/df_caverns/lava_sea.lua
index 0266497..57515b6 100644
--- a/df_caverns/lava_sea.lua
+++ b/df_caverns/lava_sea.lua
@@ -137,11 +137,6 @@ minetest.register_on_generated(function(minp, maxp, seed)
 	--write it to world
 	vm:write_to_map()
 	
-	local chunk_generation_time = math.ceil((os.clock() - t_start) * 1000) --grab how long it took
-	if chunk_generation_time < 1000 then
-		minetest.log("info", "[df_caverns] lava sea mapblock generation took "..chunk_generation_time.." ms") --tell people how long
-	else
-		minetest.log("warning", "[df_caverns] lava sea took "..chunk_generation_time.." ms to generate map block "
-			.. minetest.pos_to_string(minp) .. minetest.pos_to_string(maxp))
-	end
+	local time_taken = os.clock() - t_start -- how long this chunk took, in seconds
+	mapgen_helper.record_time("df_caverns lava sea", time_taken)
 end)
\ No newline at end of file
diff --git a/df_caverns/oil_sea.lua b/df_caverns/oil_sea.lua
index 4560c31..a5ed2d8 100644
--- a/df_caverns/oil_sea.lua
+++ b/df_caverns/oil_sea.lua
@@ -102,13 +102,8 @@ minetest.register_on_generated(function(minp, maxp, seed)
 	--write it to world
 	vm:write_to_map()
 	
-	local chunk_generation_time = math.ceil((os.clock() - t_start) * 1000) --grab how long it took
-	if chunk_generation_time < 1000 then
-		minetest.log("info", "[df_caverns] oil sea mapblock generation took "..chunk_generation_time.." ms") --tell people how long
-	else
-		minetest.log("warning", "[df_caverns] oil sea took "..chunk_generation_time.." ms to generate map block "
-			.. minetest.pos_to_string(minp) .. minetest.pos_to_string(maxp))
-	end
+	local time_taken = os.clock() - t_start -- how long this chunk took, in seconds
+	mapgen_helper.record_time("df_caverns oil sea", time_taken)
 end)
 
 minetest.register_ore({
diff --git a/df_caverns/surface_tunnels.lua b/df_caverns/surface_tunnels.lua
index a1dbc72..b4b81c4 100644
--- a/df_caverns/surface_tunnels.lua
+++ b/df_caverns/surface_tunnels.lua
@@ -77,12 +77,6 @@ minetest.register_on_generated(function(minp, maxp, seed)
 	--write it to world
 	vm:write_to_map()
 	
-	local chunk_generation_time = math.ceil((os.clock() - t_start) * 1000) --grab how long it took
-	if chunk_generation_time < 1000 then
-		minetest.log("info", "[df_caverns surface tunnels] "..chunk_generation_time.." ms") --tell people how long
-	else
-		minetest.log("warning", "[df_caverns surface tunnels] took "..chunk_generation_time.." ms to generate map block "
-			.. minetest.pos_to_string(minp) .. minetest.pos_to_string(maxp))
-	end	
-	
+	local time_taken = os.clock() - t_start -- how long this chunk took, in seconds
+	mapgen_helper.record_time("df_caverns surface tunnels", time_taken)
 end)
diff --git a/df_caverns/underworld.lua b/df_caverns/underworld.lua
index c67542c..7738be3 100644
--- a/df_caverns/underworld.lua
+++ b/df_caverns/underworld.lua
@@ -555,11 +555,6 @@ minetest.register_on_generated(function(minp, maxp, seed)
 		end
 	end
 	
-	local chunk_generation_time = math.ceil((os.clock() - t_start) * 1000) --grab how long it took
-	if chunk_generation_time < 1000 then
-		minetest.log("info", "[df_caverns] underworld mapblock generation took "..chunk_generation_time.." ms") --tell people how long
-	else
-		minetest.log("warning", "[df_caverns] underworld took "..chunk_generation_time.." ms to generate map block "
-			.. minetest.pos_to_string(minp) .. minetest.pos_to_string(maxp))
-	end
+	local time_taken = os.clock() - t_start -- how long this chunk took, in seconds
+	mapgen_helper.record_time("df_caverns underworld", time_taken)
 end)
diff --git a/mapgen_helper b/mapgen_helper
index 9c73476..ba8c4a9 160000
--- a/mapgen_helper
+++ b/mapgen_helper
@@ -1 +1 @@
-Subproject commit 9c7347691d451f6eee329cd8f7e23ccbd27bd298
+Subproject commit ba8c4a92472bc7c53708af9fade8857b44dd6f56
diff --git a/subterrane b/subterrane
index 1abfc23..4b0ae3b 160000
--- a/subterrane
+++ b/subterrane
@@ -1 +1 @@
-Subproject commit 1abfc23dd369899c1b6c4888799bcdc4525558a4
+Subproject commit 4b0ae3bce730cc88e324907e7695e719c74c913e