Set AutoScaler logic to target process scaling based on queue size wh… (#1552)

* Set AutoScaler logic to target process scaling based on queue size when balancing is disabled.

* Simplify scaling test

* Fix still using maxProcesses when runtime > 0

Author: nick-potts

src/AutoScaler.php

@@ -106,6 +106,15 @@ protected function numberOfWorkersPerQueue(Supervisor $supervisor, Collection $q
         $totalJobs = $queues->sum('size');
 
         return $queues->mapWithKeys(function ($timeToClear, $queue) use ($supervisor, $timeToClearAll, $totalJobs) {
+            if (! $supervisor->options->balancing()) {
+                $targetProcesses = min(
+                    $supervisor->options->maxProcesses,
+                    max($supervisor->options->minProcesses, $timeToClear['size'])
+                );
+
+                return [$queue => $targetProcesses];
+            }
+
             if ($timeToClearAll > 0 &&
                 $supervisor->options->autoScaling()) {
                 $numberOfProcesses = $supervisor->options->autoScaleByNumberOfJobs()

tests/Feature/AutoScalerTest.php

@@ -148,6 +148,9 @@ public function test_scaler_will_not_scale_below_minimum_worker_threshold()
         $this->assertSame(2, $supervisor->processPools['second']->totalProcessCount());
     }
 
+    /**
+     * @return array{0: AutoScaler, 1: Supervisor}
+     */
     protected function with_scaling_scenario($maxProcesses, array $pools, array $extraOptions = [])
     {
         // Mock dependencies...
@@ -258,4 +261,31 @@ public function test_scaler_assigns_more_processes_to_queue_with_more_jobs_when_
         $this->assertSame(52, $supervisor->processPools['first']->totalProcessCount());
         $this->assertSame(48, $supervisor->processPools['second']->totalProcessCount());
     }
+
+    public function test_scaler_works_with_a_single_process_pool()
+    {
+        [$scaler, $supervisor] = $this->with_scaling_scenario(10, [
+            'default' => ['current' => 10, 'size' => 1, 'runtime' => 0],
+        ], ['balance' => false]);
+
+        $scaler->scale($supervisor);
+
+        $this->assertSame(9, $supervisor->processPools['default']->totalProcessCount());
+
+        [$scaler, $supervisor] = $this->with_scaling_scenario(10, [
+            'default' => ['current' => 10, 'size' => 1, 'runtime' => 1000],
+        ], ['balance' => false]);
+
+        $scaler->scale($supervisor);
+
+        $this->assertSame(9, $supervisor->processPools['default']->totalProcessCount());
+
+        [$scaler, $supervisor] = $this->with_scaling_scenario(10, [
+            'default' => ['current' => 5, 'size' => 11, 'runtime' => 1000],
+        ], ['balance' => false]);
+
+        $scaler->scale($supervisor);
+
+        $this->assertSame(6, $supervisor->processPools['default']->totalProcessCount());
+    }
 }