From c430def90db9f8e1d7fe7b295532e7cd7232db57 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?David=20Monlla=C3=B3?= <davidm@moodle.com>
Date: Wed, 24 Jul 2019 13:58:08 +0200
Subject: [PATCH] MDL-66234 analytics: Extra GC during analysis

---
 admin/tool/analytics/classes/task/predict_models.php |  4 +++-
 admin/tool/analytics/classes/task/train_models.php   |  4 ++--
 admin/tool/analytics/cli/evaluate_model.php          |  3 ++-
 analytics/classes/analysis.php                       | 10 +++++++++-
 analytics/classes/local/analyser/base.php            |  5 +++++
 5 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/admin/tool/analytics/classes/task/predict_models.php b/admin/tool/analytics/classes/task/predict_models.php
index 6ea0d0d6356..4551e79a8a9 100644
--- a/admin/tool/analytics/classes/task/predict_models.php
+++ b/admin/tool/analytics/classes/task/predict_models.php
@@ -59,6 +59,9 @@ class predict_models extends \core\task\scheduled_task {
         }
 
         foreach ($models as $model) {
+
+            $renderer = $PAGE->get_renderer('tool_analytics');
+
             $result = $model->predict();
 
             // Reset the page as some indicators may call external functions that overwrite the page context.
@@ -66,7 +69,6 @@ class predict_models extends \core\task\scheduled_task {
 
             if ($result) {
                 echo $OUTPUT->heading(get_string('modelresults', 'tool_analytics', $model->get_name()));
-                $renderer = $PAGE->get_renderer('tool_analytics');
                 echo $renderer->render_get_predictions_results(false, array(), $result, $model->get_analyser()->get_logs());
             }
         }
diff --git a/admin/tool/analytics/classes/task/train_models.php b/admin/tool/analytics/classes/task/train_models.php
index 67c0a3a5f81..c9387d3906b 100644
--- a/admin/tool/analytics/classes/task/train_models.php
+++ b/admin/tool/analytics/classes/task/train_models.php
@@ -70,6 +70,8 @@ class train_models extends \core\task\scheduled_task {
                 continue;
             }
 
+            $renderer = $PAGE->get_renderer('tool_analytics');
+
             $result = $model->train();
 
             // Reset the page as some indicators may call external functions that overwrite the page context.
@@ -77,8 +79,6 @@ class train_models extends \core\task\scheduled_task {
 
             if ($result) {
                 echo $OUTPUT->heading(get_string('modelresults', 'tool_analytics', $model->get_name()));
-
-                $renderer = $PAGE->get_renderer('tool_analytics');
                 echo $renderer->render_get_predictions_results($result, $model->get_analyser()->get_logs());
             }
         }
diff --git a/admin/tool/analytics/cli/evaluate_model.php b/admin/tool/analytics/cli/evaluate_model.php
index 067320e196e..601599e8fd8 100644
--- a/admin/tool/analytics/cli/evaluate_model.php
+++ b/admin/tool/analytics/cli/evaluate_model.php
@@ -102,6 +102,8 @@ if ($options['reuse-prev-analysed']) {
     mtrace(get_string('evaluationinbatches', 'tool_analytics'));
 }
 
+$renderer = $PAGE->get_renderer('tool_analytics');
+
 $analyseroptions = array(
     'filter' => $options['filter'],
     'timesplitting' => $options['analysisinterval'],
@@ -114,7 +116,6 @@ $results = $model->evaluate($analyseroptions);
 // Reset the page as some indicators may call external functions that overwrite the page context.
 \tool_analytics\output\helper::reset_page();
 
-$renderer = $PAGE->get_renderer('tool_analytics');
 echo $renderer->render_evaluate_results($results, $model->get_analyser()->get_logs());
 
 // Check that we have, at leasa,t 1 valid dataset (not necessarily good) to use.
diff --git a/analytics/classes/analysis.php b/analytics/classes/analysis.php
index 32b5abe9fa7..ddb9c6fce5b 100644
--- a/analytics/classes/analysis.php
+++ b/analytics/classes/analysis.php
@@ -138,6 +138,9 @@ class analysis {
                 }
             }
         }
+
+        // Force GC to clean up the indicator instances used during the last iteration.
+        $this->analyser->instantiate_indicators();
     }
 
     /**
@@ -474,6 +477,11 @@ class analysis {
                 list($samplesfeatures, $newindicatorcalculations, $indicatornotnulls) = $rangeindicator->calculate($sampleids,
                     $this->analyser->get_samples_origin(), $range['start'], $range['end'], $prevcalculations);
 
+                // Free memory ASAP.
+                unset($rangeindicator);
+                gc_collect_cycles();
+                gc_mem_caches();
+
                 // Copy the features data to the dataset.
                 foreach ($samplesfeatures as $analysersampleid => $features) {
 
@@ -503,7 +511,7 @@ class analysis {
                         $indcalc->endtime = $range['end'];
                         $indcalc->sampleid = $sampleid;
                         $indcalc->sampleorigin = $this->analyser->get_samples_origin();
-                        $indcalc->indicator = $rangeindicator->get_id();
+                        $indcalc->indicator = $indicator->get_id();
                         $indcalc->value = $calculatedvalue;
                         $indcalc->timecreated = $timecreated;
                         $newcalculations[] = $indcalc;
diff --git a/analytics/classes/local/analyser/base.php b/analytics/classes/local/analyser/base.php
index 185f573cddb..0065f15ab85 100644
--- a/analytics/classes/local/analyser/base.php
+++ b/analytics/classes/local/analyser/base.php
@@ -246,6 +246,11 @@ abstract class base {
         foreach ($this->indicators as $key => $indicator) {
             $this->indicators[$key] = call_user_func(array($indicator, 'instance'));
         }
+
+        // Free memory ASAP.
+        gc_collect_cycles();
+        gc_mem_caches();
+
         return $this->indicators;
     }