support sandbox memory limit

test/testmemlimit.lua

@@ -0,0 +1,18 @@
+local skynet = require "skynet"
+require "skynet.manager"
+
+-- set sandbox memory limit to 1M, must set here (at start, out of skynet.start)
+skynet.memlimit(1 * 1024 * 1024)
+
+skynet.start(function()
+	local a = {}
+	local limit
+	local ok, err = pcall(function()
+		for i=1, 1000000 do
+			limit = i
+			table.insert(a, {})
+		end
+	end)
+	skynet.error(limit, err)
+	skynet.exit()
+end)