Merge pull request #246 from atopion/master

Improved performance of the cpu widget

1 files changed, 159 insertions, 122 deletions

diff --git a/cpu-widget/cpu-widget.lua b/cpu-widget/cpu-widget.lua
index bed40fe..d804c80 100644
--- a/cpu-widget/cpu-widget.lua
+++ b/cpu-widget/cpu-widget.lua
@@ -17,6 +17,9 @@ local gears = require("gears")
 local CMD = [[sh -c "grep '^cpu.' /proc/stat; ps -eo '%p|%c|%C|' -o "%mem" -o '|%a' --sort=-%cpu ]]
     .. [[| head -11 | tail -n +2"]]
 
+-- A smaller command, less resource intensive, used when popup is not shown.
+local CMD_slim = [[sh -c "grep '^cpu.' /proc/stat | head -n 1" ]]
+
 local HOME_DIR = os.getenv("HOME")
 local WIDGET_DIR = HOME_DIR .. '/.config/awesome/awesome-wm-widgets/cpu-widget'
 
@@ -111,6 +114,14 @@ local function worker(user_args)
         color = "linear:0,0:0,20:0,#FF0000:0.3,#FFFF00:0.6," .. color
     }
 
+    -- This timer periodically executes the heavy command while the popup is open.
+    -- It is stopped when the popup is closed and only the slim command is run then.
+    -- This greatly improves performance while the popup is closed at the small cost
+    -- of a slightly longer popup opening time.
+    local popup_timer = gears.timer {
+        timeout = timeout
+    }
+
     local popup = awful.popup{
         ontop = true,
         visible = false,
@@ -131,8 +142,14 @@ local function worker(user_args)
                     awful.button({}, 1, function()
                         if popup.visible then
                             popup.visible = not popup.visible
+                            -- When the popup is not visible, stop the timer
+                            popup_timer:stop()
                         else
                             popup:move_next_to(mouse.current_widget_geometry)
+                            -- Restart the timer, when the popup becomes visible
+                            -- Emit the signal to start the timer directly and not wait the timeout first
+                            popup_timer:start()
+                            popup_timer:emit_signal("timeout")
                         end
                     end)
             )
@@ -149,148 +166,168 @@ local function worker(user_args)
         widget = wibox.container.margin
     }
 
-    local cpus = {}
-    watch(CMD, timeout, function(widget, stdout)
-        local i = 1
-        local j = 1
-        for line in stdout:gmatch("[^\r\n]+") do
-            if starts_with(line, 'cpu') then
+    -- This part runs constantly, also when the popup is closed.
+    -- It updates the graph widget in the bar.
+    local maincpu = {}
+    watch(CMD_slim, timeout, function(widget, stdout)
 
-                if cpus[i] == nil then cpus[i] = {} end
+        local _, user, nice, system, idle, iowait, irq, softirq, steal, _, _ =
+            stdout:match('(%w+)%s+(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)')
 
-                local name, user, nice, system, idle, iowait, irq, softirq, steal, _, _ =
-                    line:match('(%w+)%s+(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)')
+        local total = user + nice + system + idle + iowait + irq + softirq + steal
 
-                local total = user + nice + system + idle + iowait + irq + softirq + steal
+        local diff_idle = idle - tonumber(maincpu['idle_prev'] == nil and 0 or maincpu['idle_prev'])
+        local diff_total = total - tonumber(maincpu['total_prev'] == nil and 0 or maincpu['total_prev'])
+        local diff_usage = (1000 * (diff_total - diff_idle) / diff_total + 5) / 10
 
-                local diff_idle = idle - tonumber(cpus[i]['idle_prev'] == nil and 0 or cpus[i]['idle_prev'])
-                local diff_total = total - tonumber(cpus[i]['total_prev'] == nil and 0 or cpus[i]['total_prev'])
-                local diff_usage = (1000 * (diff_total - diff_idle) / diff_total + 5) / 10
+        maincpu['total_prev'] = total
+        maincpu['idle_prev'] = idle
 
-                cpus[i]['total_prev'] = total
-                cpus[i]['idle_prev'] = idle
+        widget:add_value(diff_usage)
+    end,
+    cpugraph_widget
+    )
 
-                if i == 1 then
-                    widget:add_value(diff_usage)
-                end
+    -- This part runs whenever the timer is fired.
+    -- It therefore only runs when the popup is open.
+    local cpus = {}
+    popup_timer:connect_signal('timeout', function()
+        awful.spawn.easy_async(CMD, function(stdout, _, _, _)
+            local i = 1
+            local j = 1
+            for line in stdout:gmatch("[^\r\n]+") do
+                if starts_with(line, 'cpu') then
 
-                local row = wibox.widget
-                {
-                    create_textbox{text = name},
-                    create_textbox{text = math.floor(diff_usage) .. '%'},
-                    {
-                        max_value = 100,
-                        value = diff_usage,
-                        forced_height = 20,
-                        forced_width = 150,
-                        paddings = 1,
-                        margins = 4,
-                        border_width = 1,
-                        border_color = beautiful.bg_focus,
-                        background_color = beautiful.bg_normal,
-                        bar_border_width = 1,
-                        bar_border_color = beautiful.bg_focus,
-                        color = "linear:150,0:0,0:0,#D08770:0.3,#BF616A:0.6," .. beautiful.fg_normal,
-                        widget = wibox.widget.progressbar,
+                    if cpus[i] == nil then cpus[i] = {} end
 
-                    },
-                    layout  = wibox.layout.ratio.horizontal
-                }
-                row:ajust_ratio(2, 0.15, 0.15, 0.7)
-                cpu_rows[i] = row
-                i = i + 1
-            else
-                if is_update == true then
-
-                    local columns = split(line, '|')
-
-                    local pid = columns[1]
-                    local comm = columns[2]
-                    local cpu = columns[3]
-                    local mem = columns[4]
-                    local cmd = columns[5]
-
-                    local kill_proccess_button = enable_kill_button and create_kill_process_button() or nil
-
-                    local pid_name_rest = wibox.widget{
-                        create_textbox{text = pid},
-                        create_textbox{text = comm},
-                        {
-                            create_textbox{text = cpu, align = 'center'},
-                            create_textbox{text = mem, align = 'center'},
-                            kill_proccess_button,
-                            layout = wibox.layout.fixed.horizontal
-                        },
-                        layout  = wibox.layout.ratio.horizontal
-                    }
-                    pid_name_rest:ajust_ratio(2, 0.2, 0.47, 0.33)
+                    local name, user, nice, system, idle, iowait, irq, softirq, steal, _, _ =
+                        line:match('(%w+)%s+(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)%s(%d+)')
 
-                    local row = wibox.widget {
-                        {
-                            pid_name_rest,
-                            top = 4,
-                            bottom = 4,
-                            widget = wibox.container.margin
-                        },
-                        widget = wibox.container.background
-                    }
+                    local total = user + nice + system + idle + iowait + irq + softirq + steal
 
-                    row:connect_signal("mouse::enter", function(c) c:set_bg(beautiful.bg_focus) end)
-                    row:connect_signal("mouse::leave", function(c) c:set_bg(beautiful.bg_normal) end)
+                    local diff_idle = idle - tonumber(cpus[i]['idle_prev'] == nil and 0 or cpus[i]['idle_prev'])
+                    local diff_total = total - tonumber(cpus[i]['total_prev'] == nil and 0 or cpus[i]['total_prev'])
+                    local diff_usage = (1000 * (diff_total - diff_idle) / diff_total + 5) / 10
 
-                    if enable_kill_button then
-                        row:connect_signal("mouse::enter", function() kill_proccess_button.icon.opacity = 1 end)
-                        row:connect_signal("mouse::leave", function() kill_proccess_button.icon.opacity = 0.1 end)
+                    cpus[i]['total_prev'] = total
+                    cpus[i]['idle_prev'] = idle
 
-                        kill_proccess_button:buttons(
-                            awful.util.table.join( awful.button({}, 1, function()
-                                row:set_bg('#ff0000')
-                                awful.spawn.with_shell('kill -9 ' .. pid)
-                            end) ) )
-                    end
+                    local row = wibox.widget
+                    {
+                        create_textbox{text = name},
+                        create_textbox{text = math.floor(diff_usage) .. '%'},
+                        {
+                            max_value = 100,
+                            value = diff_usage,
+                            forced_height = 20,
+                            forced_width = 150,
+                            paddings = 1,
+                            margins = 4,
+                            border_width = 1,
+                            border_color = beautiful.bg_focus,
+                            background_color = beautiful.bg_normal,
+                            bar_border_width = 1,
+                            bar_border_color = beautiful.bg_focus,
+                            color = "linear:150,0:0,0:0,#D08770:0.3,#BF616A:0.6," .. beautiful.fg_normal,
+                            widget = wibox.widget.progressbar,
 
-                    awful.tooltip {
-                        objects = { row },
-                        mode = 'outside',
-                        preferred_positions = {'bottom'},
-                        timer_function = function()
-                            local text = cmd
-                            if process_info_max_length > 0 and text:len() > process_info_max_length then
-                                text = text:sub(0, process_info_max_length - 3) .. '...'
-                            end
-
-                            return text
-                                    :gsub('%s%-', '\n\t-') -- put arguments on a new line
-                                    :gsub(':/', '\n\t\t:/') -- java classpath uses : to separate jars
-                        end,
+                        },
+                        layout  = wibox.layout.ratio.horizontal
                     }
+                    row:ajust_ratio(2, 0.15, 0.15, 0.7)
+                    cpu_rows[i] = row
+                    i = i + 1
+                else
+                    if is_update == true then
+
+                        local columns = split(line, '|')
+
+                        local pid = columns[1]
+                        local comm = columns[2]
+                        local cpu = columns[3]
+                        local mem = columns[4]
+                        local cmd = columns[5]
+
+                        local kill_proccess_button = enable_kill_button and create_kill_process_button() or nil
+
+                        local pid_name_rest = wibox.widget{
+                            create_textbox{text = pid},
+                            create_textbox{text = comm},
+                            {
+                                create_textbox{text = cpu, align = 'center'},
+                                create_textbox{text = mem, align = 'center'},
+                                kill_proccess_button,
+                                layout = wibox.layout.fixed.horizontal
+                            },
+                            layout  = wibox.layout.ratio.horizontal
+                        }
+                        pid_name_rest:ajust_ratio(2, 0.2, 0.47, 0.33)
+
+                        local row = wibox.widget {
+                            {
+                                pid_name_rest,
+                                top = 4,
+                                bottom = 4,
+                                widget = wibox.container.margin
+                            },
+                            widget = wibox.container.background
+                        }
+
+                        row:connect_signal("mouse::enter", function(c) c:set_bg(beautiful.bg_focus) end)
+                        row:connect_signal("mouse::leave", function(c) c:set_bg(beautiful.bg_normal) end)
+
+                        if enable_kill_button then
+                            row:connect_signal("mouse::enter", function() kill_proccess_button.icon.opacity = 1 end)
+                            row:connect_signal("mouse::leave", function() kill_proccess_button.icon.opacity = 0.1 end)
+
+                            kill_proccess_button:buttons(
+                                awful.util.table.join( awful.button({}, 1, function()
+                                    row:set_bg('#ff0000')
+                                    awful.spawn.with_shell('kill -9 ' .. pid)
+                                end) ) )
+                        end
 
-                    process_rows[j] = row
+                        awful.tooltip {
+                            objects = { row },
+                            mode = 'outside',
+                            preferred_positions = {'bottom'},
+                            timer_function = function()
+                                local text = cmd
+                                if process_info_max_length > 0 and text:len() > process_info_max_length then
+                                    text = text:sub(0, process_info_max_length - 3) .. '...'
+                                end
+
+                                return text
+                                        :gsub('%s%-', '\n\t-') -- put arguments on a new line
+                                        :gsub(':/', '\n\t\t:/') -- java classpath uses : to separate jars
+                            end,
+                        }
+
+                        process_rows[j] = row
+
+                        j = j + 1
+                    end
 
-                    j = j + 1
                 end
-
             end
-        end
-        popup:setup {
-            {
-                cpu_rows,
+            popup:setup {
                 {
-                    orientation = 'horizontal',
-                    forced_height = 15,
-                    color = beautiful.bg_focus,
-                    widget = wibox.widget.separator
+                    cpu_rows,
+                    {
+                        orientation = 'horizontal',
+                        forced_height = 15,
+                        color = beautiful.bg_focus,
+                        widget = wibox.widget.separator
+                    },
+                    create_process_header{with_action_column = enable_kill_button},
+                    process_rows,
+                    layout = wibox.layout.fixed.vertical,
                 },
-                create_process_header{with_action_column = enable_kill_button},
-                process_rows,
-                layout = wibox.layout.fixed.vertical,
-            },
-            margins = 8,
-            widget = wibox.container.margin
-        }
-    end,
-    cpugraph_widget
-    )
+                margins = 8,
+                widget = wibox.container.margin
+            }
+        end)
+    end)
 
     return cpu_widget
 end