First Commit

usr/bin/topmem

@@ -0,0 +1,219 @@
+#!/usr/bin/env lua
+local f, concat, sort = string.format, table.concat, table.sort
+local found, uv = pcall(require, 'luv')
+
+local function die(err, ...)
+    print(err:format(...))
+    os.exit(1)
+end
+
+if not found then
+    die("lua-luv dependency is missing, please install it from repositories")
+end
+
+local function printf(pattern, ...)
+    print(pattern:format(...))
+end
+
+-- Patterns
+local pid_pattern = "[0-9]+"
+local ksm_profit_pattern = "ksm_process_profit%s*([0-9]+)"
+local vm_rss_pattern = "VmRSS:%s*([0-9]+)"
+local vm_swap_pattern = "VmSwap:%s*([0-9]+)"
+
+local function get_process_values(pid)
+    local path = concat({ "/proc", pid, "status" }, "/")
+    local file = io.open(path)
+
+    if not file then
+        return nil
+    end
+
+    local rss, swap
+    local line = file:read()
+    while line do
+        if rss == nil then
+            rss = line:match(vm_rss_pattern)
+        elseif swap == nil then
+            swap = line:match(vm_swap_pattern)
+        else
+            break
+        end
+        line = file:read()
+    end
+    file:close()
+    return tonumber(rss), tonumber(swap)
+end
+
+local function get_process_ksm_profit(pid)
+    local file = io.open(concat({ "/proc", pid, "ksm_stat" }, "/"))
+
+    if not file then
+        return 0
+    end
+
+    local stat = file:read("*a")
+    local profit = stat:match(ksm_profit_pattern)
+
+    file:close()
+
+    if not profit then
+        return 0
+    end
+
+    return tonumber(profit)
+end
+
+local function get_process_first_arg(pid)
+    local file = io.open(concat({ "/proc", pid, "cmdline" }, "/"))
+
+    if not file then
+        return nil
+    end
+
+    local cmdline = file:read("*all")
+    file:close()
+
+    return cmdline:match("([^%z]+)")
+end
+
+local function convert_hashmap_table(map)
+    local new_hashmap = {}
+    for key, value in pairs(map) do
+        new_hashmap[#new_hashmap + 1] = { value[1], value[2], value[3], key }
+    end
+
+    return new_hashmap
+end
+
+local function get_process_map(sort_by)
+    local map = {}
+    local processes = uv.fs_scandir("/proc")
+    local pid, ftype = uv.fs_scandir_next(processes)
+
+    while pid do
+        if pid:match(pid_pattern) then
+            if ftype == "directory" then
+                local rss, swap = get_process_values(pid)
+                local name = get_process_first_arg(pid)
+                local ksm_profit = get_process_ksm_profit(pid)
+                if name and rss then
+                    if map[name] then
+                        map[name][1] = map[name][1] + rss
+                        map[name][2] = map[name][2] + swap
+                        map[name][3] = map[name][3] + ksm_profit
+                    else
+                        map[name] = { rss, swap, ksm_profit }
+                    end
+                end
+            end
+        end
+        pid, ftype = uv.fs_scandir_next(processes)
+    end
+    map = convert_hashmap_table(map)
+    sort(map, function(a, b) return (a[sort_by] > b[sort_by]) end)
+    return map
+end
+
+local function truncate(str)
+    if #str > 25 then
+        return str:sub(1, 25) .. "..."
+    else
+        return str
+    end
+end
+
+local function get_filename(path)
+    local lastSlash = path:find("/[^/]*$")
+    if lastSlash then
+        return path:sub(lastSlash + 1)
+    else
+        return path
+    end
+end
+
+local function print_top(size, sort_by)
+    local map = get_process_map(sort_by)
+    printf("%-9s %35s %-9s %-s", "MEMORY", "Top " .. size .. " processes       ", "SWAP", "KSM")
+    for i = 1, size do
+        local entry = map[i]
+        if entry then
+            printf(
+                "%-9s %-35s %-9s %-s",
+                f("%.0f", entry[1] / 1024) .. "M",
+                truncate(get_filename(entry[4])),
+                f("%.0f", entry[2] / 1024) .. "M",
+                f("%.0f", entry[3] / 1024 / 1024) .. "M"
+            )
+        end
+    end
+end
+
+local function print_help()
+    print([[
+Shows names of the top 10 (or N) processes by memory consumption
+
+Usage: topmem [OPTIONS] [N]
+
+Arguments:
+  [N] [default: 10]
+
+Options:
+  -s, --sort <TYPE>  Column to sort by [possible values: rss (default), swap, ksm]
+  -h, --help         Show this message]]
+)
+    os.exit(0)
+end
+
+local function main()
+    local sort_types = {
+        ["rss"] = 1,
+        ["swap"] = 2,
+        ["ksm"] = 3
+    }
+    local sort_by = sort_types["rss"]
+    local size
+    local i = 1
+    while i < #arg + 1 do
+        if arg[i] == "--sort" or arg[i] == "-s" or arg[i]:match("--sort=*") then
+            local criteria
+            local shift = true
+
+            for value in string.gmatch(arg[i], "([^=]+)") do
+                if value ~= "--sort" and value ~= "-s" then
+                    criteria = value
+                    shift = false
+                    break
+                end
+            end
+
+            criteria = criteria or arg[i + 1]
+            if not criteria then
+                die("Column to sort by is not specified")
+            end
+
+            if not sort_types[criteria] then
+                die("Wrong sorting criterion. Only available: rss, swap, ksm.")
+            else
+                sort_by = sort_types[criteria]
+                if shift then
+                    i = i + 1
+                end
+            end
+        elseif arg[i] == "--help" or arg[i] == "-h" then
+            print_help()
+        else
+            local status, value = pcall(tonumber, arg[i])
+            if not status then
+                die("The argument must be a number")
+            else
+                size = value
+            end
+        end
+        i = i + 1
+    end
+
+    print_top(size or 10, sort_by)
+end
+
+main()