ENH make gpu power limits configurable

config/config.dhall

@@ -138,6 +138,23 @@ let FileSystem =
       , default.geometry = FSGeo::{=}
       }
 
+let GPUPower =
+    {-
+    Controls how the GPU will be queries so it can go to sleep when 'idle'.
+
+    freq_limit: only query the GPU every 'cycle_seconds' when frequency is below
+                this value; this should be a sensible value representing and
+                'idle' gpu state.
+    cycle_seconds: the number of seconds to query the GPU when below the idle
+                   frequency limit; note that this must be long enough to let
+                   the GPU go to sleep when it actually is ready to sleep, but
+                   not so long that the next query will miss too much activity
+                   in the case the GPU doesn't shut off
+    -}
+      { Type = { freq_limit : Natural, cycle_seconds : Natural }
+      , default = { freq_limit = 250, cycle_seconds = 10 }
+      }
+
 let Graphics =
     {-
     Defines Graphics module configuration
@@ -158,8 +175,9 @@ let Graphics =
           , show_mem_util : Bool
           , show_vid_util : Bool
           , geometry : GfxGeo.Type
+          , power : GPUPower.Type
           }
-      , default.geometry = GfxGeo::{=}
+      , default = { geometry = GfxGeo::{=}, power = GPUPower::{=} }
       }
 
 let Memory =

src/modules/graphics.lua

@@ -20,29 +20,43 @@ return function(update_freq, config, common, width, point)
 
    i_o.assert_exe_exists(NVIDIA_EXE)
 
-   -- vars to process the nv settings glob
-   --
+   local mk_query_cmd = function(props)
+      return string.format(
+         '%s --query-gpu=%s --format=csv,noheader,nounits',
+         NVIDIA_EXE,
+         pure.collapse(props, ',')
+      )
+   end
 
-   local NV_QUERY = NVIDIA_EXE..
-      ' --query-gpu=memory.used,memory.total,temperature.gpu,clocks.gr,clocks.mem,utilization.gpu,utilization.decoder'..
-      ' --format=csv,noheader,nounits'
+   -- TODO also use encoder for video util?
+   -- TODO add video clock speed?
+   local query_stats = mk_query_cmd(
+      {
+         'memory.used',
+         'temperature.gpu',
+         'clocks.gr',
+         'clocks.mem',
+         'utilization.gpu',
+         'utilization.decoder'
+      }
+   )
 
-   local NV_REGEX = '(%d+), (%d+), (%d+), (%d+), (%d+), (%d+), (%d+)'
+   local NV_REGEX = '(%d+), (%d+), (%d+), (%d+), (%d+), (%d+)'
 
    local mod_state = {
       error = false,
+      total_memory = 0,
       gpu_frequency = 0,
       memory_frequency = 0,
       used_memory = 0,
-      total_memory = 0,
       temp_reading = 0,
       gpu_utilization = 0,
       vid_utilization = 0
    }
 
    local sleep_token = 0
-   local sleep_limit = 10
-   local gpu_idle_freq_limit = 250
+   local sleep_limit = config.power.cycle_seconds
+   local gpu_idle_freq_limit = config.power.freq_limit
 
    -- TODO ensure this file exists
    local runtime_status_file = config.dev_power..'/runtime_status'
@@ -74,12 +88,11 @@ return function(update_freq, config, common, width, point)
          sleep_token = 0
       end
       if is_active and want_nvidia_query and sleep_token == 0 then
-         local nvidia_settings_glob = i_o.execute_cmd(NV_QUERY)
+         local nvidia_settings_glob = i_o.execute_cmd(query_stats)
          if nvidia_settings_glob == nil then
             mod_state.error = 'Error'
          else
             mod_state.used_memory,
-               mod_state.total_memory,
                mod_state.temp_reading,
                mod_state.gpu_frequency,
                mod_state.memory_frequency,
@@ -89,6 +102,11 @@ return function(update_freq, config, common, width, point)
             mod_state.gpu_frequency = tonumber(mod_state.gpu_frequency)
             mod_state.error = false
          end
+         -- query total memory if we need it (do this here so we don't turn on
+         -- the gpu every time we start conky)
+         if mod_state.total_memory == 0 and config.show_mem_util then
+            mod_state.total_memory = tonumber(i_o.execute_cmd(mk_query_cmd({'memory.total'})))
+         end
       elseif is_active then
          mod_state.error = false
       else

src/pure.lua

@@ -4,6 +4,7 @@ local err = require 'err'
 
 local __math_floor = math.floor
 local __table_insert = table.insert
+local __string_format = string.format
 
 --------------------------------------------------------------------------------
 -- zippy functions
@@ -50,9 +51,52 @@ M.reduce = function(f, init, seq)
    end
 end
 
+M.member = function(x, seq)
+   return M.reduce(
+      function(acc, next) return acc or next == x end,
+      false,
+      M.values(seq)
+   )
+end
+
+M.collapse = function(seq, delim)
+   if #seq == 0 then
+      return ''
+   elseif #seq == 1 then
+      return seq[1]
+   else
+      local init, rest = M.head(seq)
+      return M.reduce(
+         function(acc, next) return __string_format('%s%s%s', acc, delim, next) end,
+         init,
+         rest
+      )
+   end
+end
+
 --------------------------------------------------------------------------------
 -- mappy functions
 
+M.keys = function(seq)
+   local r = {}
+   local n = 1
+   for k, _ in pairs(seq) do
+      r[n] = k
+      n = n + 1
+   end
+   return r
+end
+
+M.values = function(seq)
+   local r = {}
+   local n = 1
+   for _, v in pairs(seq) do
+      r[n] = v
+      n = n + 1
+   end
+   return r
+end
+
 M.map = function(f, seq, ...)
    local r = {}
    for i = 1, #seq do
@@ -144,6 +188,14 @@ M.length = function(tbl)
    return n
 end
 
+M.head = function(seq)
+   local r = {}
+   for i = 2, #seq do
+      r[i - 1] = seq[i]
+   end
+   return seq[1], r
+end
+
 -- a stupid but composable function
 M.get = function(key, tbl)
    return tbl[key]