How to Solve: "Could not acquire lock for cron job: X" in Magento var/log/cron.log

Question

With my M2 instance indexers in "Update on Schedule" mode... var/log/cron.log receives this warning near constantly:

Could not acquire lock for cron job: indexer_update_all_views [] []

The cron process in the process list terminates... plus I have a constant "X in the backlog" message for a few indexes.

I cannot figure out what this problem is about... I've tried truncating all *_cl tables and rebuilding the index... but still the site eventually goes back to items permanently stuck the backlog, a cron job not terminating, and this log message always appearing.

The only solution I have right now to restore the site's performance is to leave the indexer in Update on Save mode.

Thoughts?

Answer 1

Same thing here on 2.3.5 . Any solution would be nice.

My catalogsearch_fulltext is constantly running it seems (every run takes about 6 minutes). Maybe related? Using Elasticsearch. Maybe it is just a warning, because the search process is still running?

Answer 2

Before doing this, disable crons and enter maintenance mode.

I ended up truncating all _cl tables. Then I ran UPDATE mview_state SET version_id = '0'; in order to reset all statusses and versions to their starting position. In my case they did not increment anymore and index_all_invalid gave the lock error.

Then truncate cron_schedule

After this, reset/reindex from cli, clear cache, disable maintenance and re-enable crons.

In my case: after migration I had a lot of attributes that had their values saved per storeview (not using default setting anymore). I think that caused a lot of troubles.

Anyway before I did the above, I cleaned out a lot of product and category rubble (attribute_id where store_id <> 0 in entity varchar, text, int, decimal, mediagallery, datetime, etc.

Hope it works for you or points you in the right direction.

Answer 3

I fixed it in Magento 2.3 changing the cron schedule as you can see below.

Then I ran this command in the database.

TRUNCATE TABLE `cataloginventory_stock_cl`;
TRUNCATE TABLE `catalogrule_product_cl`;
TRUNCATE TABLE `catalogrule_rule_cl`;
TRUNCATE TABLE `catalogsearch_fulltext_cl`;
TRUNCATE TABLE `catalog_category_product_cl`;
TRUNCATE TABLE `catalog_product_attribute_cl`;
TRUNCATE TABLE `catalog_product_category_cl`;
TRUNCATE TABLE `catalog_product_price_cl`;
TRUNCATE TABLE `customer_dummy_cl`;
TRUNCATE TABLE `design_config_dummy_cl`;
TRUNCATE TABLE `salesrule_rule_cl`;
TRUNCATE TABLE `targetrule_product_rule_cl`;
TRUNCATE TABLE `targetrule_rule_product_cl`;
TRUNCATE TABLE `inventory_cl`;

/* reset view_state */
UPDATE `mview_state` SET `version_id` = '0';

/* reset cron jobs schedule */
TRUNCATE TABLE `cron_schedule`;

And in the root folder I ran it:

wget https://files.magerun.net/n98-magerun2.phar && chmod +x ./n98-magerun2.phar && alias n98="PHP -d memory_limit=-1 ./n98-magerun2.phar"
n98 index:reset;
n98 index:reindex;
n98 cache:flush;

If you wanna understand better this solution, you can check these references:

• https://github.com/magento/magento2/issues/5836
• https://www.vannoortproductions.nl/magento-2-indexer-stuck-at-processing/