Magento 2 cron jobs — waarom je shop 's nachts vastloopt

# Magento cron — minimale configuratie
* * * * * www-data php /var/www/html/bin/magento cron:run 2>&1 | grep -v "Ran jobs by schedule"
* * * * * www-data php /var/www/html/bin/magento cron:run --group index 2>&1 | grep -v "Ran jobs by schedule"

<!-- etc/crontab.xml in een module -->
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Cron:etc/crontab.xsd">
    <group id="default">
        <job name="vendor_module_sync" instance="Vendor\Module\Cron\Sync" method="execute">
            <schedule>0 2 * * *</schedule>
        </job>
    </group>
</config>

-- Controleer hoeveel cron jobs tegelijk lopen
SELECT job_code, status, COUNT(*) as count
FROM cron_schedule
WHERE status = 'running'
GROUP BY job_code, status
ORDER BY count DESC;

<!-- Configureer in app/etc/env.php of via admin -->
'cron_groups' => [
    'default' => [
        'schedule_generate_every' => 15,
        'schedule_ahead_for' => 20,
        'schedule_lifetime' => 15,
        'history_cleanup_every' => 10,
        'history_success_lifetime' => 10080,
        'history_failure_lifetime' => 10080,
        'use_separate_process' => 1,
        'max_running_jobs' => 3,
    ],
]

-- Recente cron-geschiedenis
SELECT job_code, status, scheduled_at, executed_at, finished_at,
       TIMESTAMPDIFF(SECOND, executed_at, COALESCE(finished_at, NOW())) as duration_seconds,
       messages
FROM cron_schedule
WHERE scheduled_at > NOW() - INTERVAL 24 HOUR
ORDER BY scheduled_at DESC
LIMIT 100;

# Bekijk lopende PHP-processen
ps aux | grep "cron:run" | grep -v grep

# Bekijk hoeveel processen er zijn
ps aux | grep "cron:run" | grep -v grep | wc -l

# Magento cron log
tail -f /var/www/html/var/log/cron.log

# System log op fouten
tail -f /var/www/html/var/log/system.log | grep -i "cron\|error\|critical"

# PHP process monitor
grep "cron" /var/log/php-fpm/error.log | tail -50

-- Welke queries lopen tijdens cron-piek
SHOW PROCESSLIST;

-- Slow queries gerelateerd aan cron
SELECT query_time, sql_text
FROM mysql.slow_log
WHERE sql_text LIKE '%cron%'
ORDER BY query_time DESC
LIMIT 20;

# PHP memory limit voor CLI processen
# In php.ini of via .htaccess
memory_limit = 2G

# Of per job controleren
php -d memory_limit=4G bin/magento cron:run --group index

// Zware cron jobs: geef het geheugen terug per batch
public function execute(): void
{
    $collection = $this->productCollectionFactory->create();
    $collection->setPageSize(500);
    $lastPage = $collection->getLastPageNumber();

    for ($page = 1; $page <= $lastPage; $page++) {
        $collection->setCurPage($page)->load();

        foreach ($collection as $product) {
            $this->processProduct($product);
        }

        // Geef geheugen vrij na elke batch
        $collection->clear();
        gc_collect_cycles();
    }
}

<!-- Goede spreiding: meerdere imports op verschillende tijden -->
<job name="import_products" ...>
    <schedule>0 1 * * *</schedule>  <!-- 01:00 -->
</job>
<job name="import_prices" ...>
    <schedule>0 2 * * *</schedule>  <!-- 02:00 -->
</job>
<job name="import_stock" ...>
    <schedule>30 2 * * *</schedule> <!-- 02:30 -->
</job>

#!/bin/bash
# check-cron.sh — draai dit elke 15 minuten via systeemcron

ZOMBIE_THRESHOLD=10
RUNNING=$(ps aux | grep "cron:run" | grep -v grep | wc -l)

if [ "$RUNNING" -gt "$ZOMBIE_THRESHOLD" ]; then
    echo "ALARM: $RUNNING cron processen actief" | mail -s "Magento cron alarm" [email protected]
fi

# Check op stuck running jobs
STUCK=$(mysql -u magento -p"$DB_PASS" magento -e "
    SELECT COUNT(*) FROM cron_schedule
    WHERE status = 'running'
    AND executed_at < NOW() - INTERVAL 2 HOUR;" -s -N)

if [ "$STUCK" -gt "0" ]; then
    echo "ALARM: $STUCK cron jobs al 2+ uur in running status" | mail -s "Magento cron stuck" [email protected]
fi

-- Handmatig opruimen van oude cron history
DELETE FROM cron_schedule
WHERE scheduled_at < NOW() - INTERVAL 7 DAY
AND status IN ('success', 'missed');