Merge pull request #5251 from miqrogroove/patch-1

Unify Worker Load Formulas

diff --git a/doc/htconfig.md b/doc/htconfig.md
index 50fc4255fbc6d39df1dd62e0d00a7f9fd96c47a1..296551244cba24f269020f41767d3d75ab830c83 100644 (file)
--- a/doc/htconfig.md
+++ b/doc/htconfig.md
@@ -94,7 +94,7 @@ Example: To set the automatic database cleanup process add this line to your .ht
 * **throttle_limit_month** - Maximum number of posts that a user can send per month with the API.
 * **wall-to-wall_share** (Boolean) - Displays forwarded posts like "wall-to-wall" posts.
 * **worker_cooldown** - Cooldown time after each worker function call. Default value is 0 seconds.
-* **worker_linear_load** (Boolean) - Enables the linear calculation of maximum queues.
+* **worker_load_exponent** (Integer) - Default 3, which allows only 25% of the maximum worker queues when server load reaches around 37% of maximum load.  For a linear response where 25% of worker queues are allowed at 75% of maximum load, set this to 1.  Setting 0 would allow maximum worker queues at all times, which is not recommended.
 * **xrd_timeout** - Timeout for fetching the XRD links. Default value is 20 seconds.
 
 ## experimental ##

diff --git a/src/Core/Worker.php b/src/Core/Worker.php
index bc45be2d5b75da128966c7d98d56d0cb3dda2315..c965e05830adee089e5d928dc14eb9ad164efd40 100644 (file)
--- a/src/Core/Worker.php
+++ b/src/Core/Worker.php
@@ -625,34 +625,14 @@ class Worker
                if ($load) {
                        $maxsysload = intval(Config::get("system", "maxloadavg", 50));
 
-                       if (Config::get('system', 'worker_linear_load', false)) {
-                               /* The linear load calculation works fine if there is a low
-                                * number of maximum queues and a high load base level.
-                                * This can be present at shared hosters.
-                               */
-                               $tinyload = 1;
-
-                               if ($load > $maxsysload) {
-                                       $queues = 0;
-                               } elseif ($load > $tinyload) {
-                                       //Provide $queues number between 1 (below max load) and $maxqueues - 1 (above tiny load).
-                                       $range = $maxsysload - $tinyload;
-                                       $slope = 1.00 - (($load - $tinyload) / $range);
-                                       $target = $slope * ($maxqueues - 1);
-                                       $queues = intval(ceil($target));
-                               }
-                       } else {
-                               /* The exponentional load calculation respects the load behaviour
-                                * of Linux systems with regular hardware that normally idles
-                                * with load values near 0.
-                               */
-                               $maxworkers = $queues;
-
-                               // Some magical mathemathics to reduce the workers
-                               $exponent = 3;
-                               $slope = $maxworkers / pow($maxsysload, $exponent);
-                               $queues = ceil($slope * pow(max(0, $maxsysload - $load), $exponent));
-                       }
+                       /* Default exponent 3 causes queues to rapidly decrease as load increases.
+                        * If you have 20 max queues at idle, then you get only 5 queues at 37.1% of $maxsysload.
+                        * For some environments, this rapid decrease is not needed.
+                        * With exponent 1, you could have 20 max queues at idle and 13 at 37% of $maxsysload.
+                        */
+                       $exponent = intval(Config::get('system', 'worker_load_exponent', 3));
+                       $slope = pow(max(0, $maxsysload - $load) / $maxsysload, $exponent);
+                       $queues = intval(ceil($slope * $maxqueues));
 
                        $processlist = '';