Add mtos cache in ram to boost performance

API.md

@@ -207,7 +207,8 @@ Can be used for non-data and/or system tasks. For usual data store please use th
 - `bdev:get_hard_disk()` hdd store - a table with all app-related storage partitions, if hard disk capatibility exists
 - `bdev:get_removable_disk()` removable data object (drive)
 - `bdev:get_cloud_disk(storage_name)` - Get named cloud storage
-- `bdev:sync()` - Write/store all opened and maybe changed data
+- `bdev:sync()` - Write/store all opened and maybe changed data (cached)
+- `bdev:sync_cloud()` - Write/store all opened and maybe changed data in cloud
 
 ### Storage methods
 - `get_boot_disk()` - Check which device can be booted. possible return value is "hdd" or "removable"

apps/removable_app.lua

@@ -58,5 +58,6 @@ laptop.register_app("removable", {
 			end
 		end
 		mtos.bdev:sync()
+		laptop.mtos_cache:free(mtos.pos)
 	end,
 })

block_devices.lua

@@ -178,7 +178,10 @@ function bdev:sync()
 		end
 		self.removable_disk.inv:set_stack("main", 1, self.removable_disk.stack)
 	end
+end
 
+-- Save all data if used
+function bdev:sync_cloud()
 	-- Modmeta (Cloud)
 	if self.cloud_disk then
 		for store, value in pairs(self.cloud_disk) do

hardware_fw.lua

@@ -2,6 +2,7 @@
 laptop.node_config = {}
 
 local function on_construct(pos)
+	laptop.mtos_cache:free(pos)
 	local mtos = laptop.os_get(pos)
 	local node = minetest.get_node(pos)
 	local hwdef = laptop.node_config[node.name]
@@ -15,6 +16,10 @@ local function on_construct(pos)
 	end
 end
 
+local function after_destruct(pos, oldnode)
+	laptop.mtos_cache:free(pos)
+end
+
 local function on_punch(pos, node, puncher)
 	local mtos = laptop.os_get(pos)
 
@@ -36,6 +41,7 @@ local function on_punch(pos, node, puncher)
 		-- reload OS
 		slot:reload(punch_item)
 		mtos.bdev:sync()
+		laptop.mtos_cache:free(pos)
 		for k,v in pairs(laptop.os_get(mtos.pos)) do
 			mtos[k] = v
 		end
@@ -186,6 +192,7 @@ function laptop.register_hardware(name, hwdef)
 --		def.preserve_metadata = preserve_metadata TODO: if MT-0.5 stable
 		def.on_punch = on_punch
 		def.on_construct = on_construct
+		def.after_destruct = after_destruct
 		def.on_receive_fields = on_receive_fields
 		def.allow_metadata_inventory_move = allow_metadata_inventory_move
 		def.allow_metadata_inventory_put = allow_metadata_inventory_put

mtos.lua

@@ -64,6 +64,65 @@ laptop.supported_textcolors = {
 }
 
 
+-----------------------------------------------------
+-- Operating System cache
+-----------------------------------------------------
+local mtos_cache = {
+	list = {},
+	is_running = false
+}
+laptop.mtos_cache = mtos_cache
+
+function mtos_cache:get(pos)
+	local hash = minetest.hash_node_position(pos)
+	return self.list[hash]
+end
+
+function mtos_cache:set(pos, mtos)
+	local hash = minetest.hash_node_position(pos)
+	mtos.last_access = os.time()
+	self.list[hash] = mtos
+	self:check_free_step()
+end
+
+function mtos_cache:free(pos)
+	local hash = minetest.hash_node_position(pos)
+	self.list[hash] = nil
+end
+
+function mtos_cache:check_free_step()
+	-- do not start twice
+	if self.is_running then
+		return
+	end
+
+	local function check_free(mtos_cache)
+		local current_time
+		for hash, mtos in pairs(mtos_cache.list) do
+			current_time = current_time or os.time()
+			if mtos.last_access +5 < current_time then -- 5 seconds cache
+				mtos.bdev:sync()
+				mtos_cache:free(mtos.pos)
+			end
+		end
+		mtos_cache.is_running = false
+		mtos_cache:check_free_step()
+	end
+
+	if next(self.list) then
+		self.is_running = true
+		minetest.after(1, check_free, self)
+	end
+end
+
+-- Sync all on shutdown
+minetest.register_on_shutdown(function()
+	for hash, mtos in pairs(mtos_cache.list) do
+		mtos.bdev:sync()
+		mtos_cache:free(mtos.pos)
+	end
+end)
+
 -----------------------------------------------------
 -- Operating System class
 -----------------------------------------------------
@@ -89,6 +148,7 @@ end
 -- Power on the system and start the launcher
 function os_class:power_on(new_node_name)
 	self.bdev:free_ram_disk()
+	mtos_cache:free(self.pos)
 	-- update current instance with reinitialized data
 	for k,v in pairs(laptop.os_get(self.pos)) do
 		self[k] = v
@@ -292,7 +352,8 @@ function os_class:pass_to_app(method, reshow, sender, ...)
 end
 
 function os_class:save()
-	self.bdev:sync()
+	self.bdev:sync_cloud()
+	mtos_cache:set(self.pos, self)
 end
 
 -- Use parameter and launch the select_file dialog
@@ -315,7 +376,14 @@ end
 -- Get Operating system object
 -----------------------------------------------------
 function laptop.os_get(pos)
-	local self = setmetatable({}, os_class)
+	-- get OS-object from cache
+	local self = mtos_cache:get(pos)
+	if self then
+		return self
+	end
+
+	-- Create new if not in cache
+	self = setmetatable({}, os_class)
 	self.__index = os_class
 	self.pos = pos
 	self.node = minetest.get_node(pos)