module:set_global()

local get_cpu_time = os.clock

local custom_metric = require "core.statsmanager".metric

local cpu_time = custom_metric(

	"counter", "process_cpu", "seconds",

	"CPU time used by Prosody as reported by clock(3)."

):with_labels()

local lfs = require "lfs"

module:hook("stats-update", function ()

	cpu_time:set(get_cpu_time())

end);

if lfs.attributes("/proc/self/statm", "mode") == "file" then

	local pagesize = module:get_option_number("memory_pagesize", 4096); -- getconf PAGESIZE

	local vsz = custom_metric(

		"gauge", "process_virtual_memory", "bytes",

		"Virtual memory size in bytes."

	):with_labels()

	local rss = custom_metric(

		"gauge", "process_resident_memory", "bytes",

		"Resident memory size in bytes."

	):with_labels()

	module:hook("stats-update", function ()

		local statm, err = io.open("/proc/self/statm");

		if not statm then

			module:log("error", tostring(err));

			return;

		end

		-- virtual memory (caches, opened librarys, everything)

		vsz:set(statm:read("*n") * pagesize);

		-- resident set size (actually used memory)

		rss:set(statm:read("*n") * pagesize);

		statm:close();

	end);

end

if lfs.attributes("/proc/self/fd", "mode") == "directory" then

	local open_fds = custom_metric(

		"gauge", "process_open_fds", "",

		"Number of open file descriptors."

	):with_labels()

	local has_posix, posix = pcall(require, "util.pposix")

	local max_fds

	if has_posix then

		max_fds = custom_metric(

			"gauge", "process_max_fds", "",

			"Maximum number of open file descriptors"

		):with_labels()

	else

		module:log("warn", "not reporting maximum number of file descriptors because mod_posix is not available")

	end

	local function limit2num(limit)

		if limit == "unlimited" then

			return math.huge

		end

		return limit

	end

	module:hook("stats-update", function ()

		local count = 0

		for _ in lfs.dir("/proc/self/fd") do

			count = count + 1

		end

		open_fds:set(count)

		if has_posix then

			local ok, soft, hard = posix.getrlimit("NOFILE")

			if ok then

				max_fds:set(limit2num(soft or hard));

			end

		end

	end);

end