1 files changed, 83 insertions, 0 deletions
diff --git a/context.lua b/context.lua
new file mode 100644
index 0000000..1bdb338
--- /dev/null
+++ b/context.lua
@@ -0,0 +1,83 @@
+local has_monitoring = minetest.get_modpath("monitoring")
+
+local mapblock_count, penalized_mapblock_count
+
+if has_monitoring then
+	mapblock_count = monitoring.gauge("mesecons_debug_mapblock_count", "count of tracked mapblocks")
+	penalized_mapblock_count = monitoring.gauge("mesecons_debug_penalized_mapblock_count", "count of penalized mapblocks")
+end
+
+local function get_blockpos(pos)
+	return {x = math.floor(pos.x / 16),
+	        y = math.floor(pos.y / 16),
+	        z = math.floor(pos.z / 16)}
+end
+
+-- blockpos-hash => context
+local context_store = {}
+
+mesecons_debug.get_context = function(pos)
+  local blockpos = get_blockpos(pos)
+  local hash = minetest.hash_node_position(blockpos)
+
+  local ctx = context_store[hash]
+  if not ctx then
+    -- create a new context
+    ctx = {
+      -- usage in us
+      micros = 0,
+      -- average micros per second
+      avg_micros = 0,
+      -- time penalty
+      penalty = 0,
+
+			-- mtime
+			mtime = minetest.get_us_time(),
+    }
+    context_store[hash] = ctx
+  end
+
+  return ctx
+end
+
+local timer = 0
+minetest.register_globalstep(function(dtime)
+  timer = timer + dtime
+  if timer < 1 then return end
+  timer=0
+
+	local penalized_count = 0
+	local now = minetest.get_us_time()
+	local cleanup_time_micros = 300 * 1000 * 1000
+
+  mesecons_debug.context_store_size = 0
+  for hash, ctx in pairs(context_store) do
+		local time_diff = now - ctx.mtime
+		if time_diff > cleanup_time_micros then
+			-- remove item
+			context_store[hash] = nil
+
+		else
+			-- calculate stuff
+			ctx.avg_micros = math.floor((ctx.avg_micros * 0.9) + (ctx.micros * 0.1))
+	    ctx.micros = 0
+	    if ctx.avg_micros > mesecons_debug.max_usage_micros then
+				-- add penalty
+	      ctx.penalty = math.min(ctx.penalty + 0.1, 20)
+	    elseif ctx.penalty > 0 then
+				-- remove penalty (slowly)
+	      ctx.penalty = math.max(ctx.penalty - 0.01, 0)
+	    end
+
+	    mesecons_debug.context_store_size = mesecons_debug.context_store_size + 1
+			if ctx.penalty > 0 then
+				penalized_count = penalized_count + 1
+			end
+
+		end
+  end
+
+	mapblock_count.set(mesecons_debug.context_store_size)
+	penalized_mapblock_count.set(penalized_count)
+
+end)