From 9277a27ce4527ea17cebb9529f26203650d09056 Mon Sep 17 00:00:00 2001
From: Matthew Wild <mwild1@gmail.com>
Date: Mon, 15 Jun 2020 14:16:10 +0100
Subject: util.gc: New module for configuring the Lua garbage collector

---
 util/gc.lua | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 util/gc.lua

diff --git a/util/gc.lua b/util/gc.lua
new file mode 100644
index 00000000..e02e85c4
--- /dev/null
+++ b/util/gc.lua
@@ -0,0 +1,50 @@
+local array = require "util.array";
+local set = require "util.set";
+
+local known_options = {
+	incremental = set.new { "mode", "threshold", "speed", "step_size" };
+	generational = set.new { "mode", "minor_threshold", "major_threshold" };
+};
+
+if _VERSION ~= "5.4" then
+	known_options.generational = nil;
+	known_options.incremental:remove("step_size");
+end
+
+local function configure(user, defaults)
+	local mode = user.mode or defaults.mode or "incremental";
+	if not known_options[mode] then
+		return nil, "GC mode not supported on ".._VERSION..": "..mode;
+	end
+
+	for k, v in pairs(user) do
+		if not known_options[mode]:contains(k) then
+			return nil, "Unknown GC parameter: "..k;
+		elseif k ~= "mode" and type(v) ~= "number" then
+			return nil, "parameter '"..k.."' should be a number";
+		end
+	end
+
+	if mode == "incremental" then
+		if _VERSION == "Lua 5.4" then
+			collectgarbage(mode,
+				user.threshold or defaults.threshold,
+				user.speed or defaults.speed,
+				user.step_size or defaults.step_size
+			);
+		else
+			collectgarbage("setpause", user.threshold or defaults.threshold);
+			collectgarbage("setstepmul", user.speed or defaults.speed);
+		end
+	elseif mode == "generational" then
+		collectgarbage(mode,
+			user.minor_threshold or defaults.minor_threshold,
+			user.major_threshold or defaults.major_threshold
+		);
+	end	
+	return true;
+end
+
+return {
+	configure = configure;
+};
-- 
cgit v1.2.3


From 42ff12bb04548d882b06d5d3de198aa9e74d9081 Mon Sep 17 00:00:00 2001
From: Matthew Wild <mwild1@gmail.com>
Date: Mon, 15 Jun 2020 14:23:47 +0100
Subject: util.gc: Linter fixes [luacheck]

---
 util/gc.lua | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/util/gc.lua b/util/gc.lua
index e02e85c4..b400af6b 100644
--- a/util/gc.lua
+++ b/util/gc.lua
@@ -1,4 +1,3 @@
-local array = require "util.array";
 local set = require "util.set";
 
 local known_options = {
@@ -41,7 +40,7 @@ local function configure(user, defaults)
 			user.minor_threshold or defaults.minor_threshold,
 			user.major_threshold or defaults.major_threshold
 		);
-	end	
+	end
 	return true;
 end
 
-- 
cgit v1.2.3


From c313b10cd98e8461bc1f17c6e7f47e90e0d3c379 Mon Sep 17 00:00:00 2001
From: Matthew Wild <mwild1@gmail.com>
Date: Mon, 15 Jun 2020 14:16:34 +0100
Subject: util.startup: Configure the GC on startup, using the config or
 built-in defaults

---
 util/startup.lua | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/util/startup.lua b/util/startup.lua
index 2a7e8a36..c1f4ec8b 100644
--- a/util/startup.lua
+++ b/util/startup.lua
@@ -12,6 +12,8 @@ local dependencies = require "util.dependencies";
 
 local original_logging_config;
 
+local default_gc_params = { mode = "incremental", threshold = 105, speed = 250 };
+
 local short_params = { D = "daemonize", F = "no-daemonize" };
 local value_params = { config = true };
 
@@ -544,6 +546,19 @@ function startup.check_unwriteable()
 	end
 end
 
+function startup.init_gc()
+	-- Apply garbage collector settings from the config file
+	local gc = require "util.gc";
+	local gc_settings = config.get("*", "gc") or { mode = default_gc_params.mode };
+
+	local ok, err = gc.configure(gc_settings, default_gc_params);
+	if not ok then
+		log("error", "Failed to apply GC configuration: %s", err);
+		return nil, err;
+	end
+	return true;
+end
+
 function startup.make_host(hostname)
 	return {
 		type = "local",
@@ -573,6 +588,7 @@ function startup.prosodyctl()
 	startup.read_config();
 	startup.force_console_logging();
 	startup.init_logging();
+	startup.init_gc();
 	startup.setup_plugindir();
 	startup.setup_datadir();
 	startup.chdir();
@@ -593,6 +609,7 @@ function startup.prosody()
 	startup.init_global_state();
 	startup.read_config();
 	startup.init_logging();
+	startup.init_gc();
 	startup.sanity_check();
 	startup.sandbox_require();
 	startup.set_function_metatable();
-- 
cgit v1.2.3