How to configure the indexer to run over the night?

Question

I would like to run my indexer to run over the night since I'm already using the reindex by schedule, how could I do that?

Answer 1

Changing the schedule

Create a module with the file etc/crontab.xml with the content below to override the default index job and schedule it to run every day at 9 pm.

<?xml version="1.0"?>
<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="indexer_reindex_all_invalid" instance="Magento\Indexer\Cron\ReindexAllInvalid" method="execute">
            <schedule>0 */21 * * *</schedule>
        </job>
    </group>
</config>

Checking the current schedule

You might use the n98-magerun2 to check the actual schedule as the image below shows.

n98-magerun.phar sys:cron:list