Moodle 4.1 Memcached issues

Moodle 4.1 Memcached issues

Jaco-Louis Kruger -
回帖数:6

Hi Moodlers

We have a Moodle architecture hosted in AWS and we recently upgraded to Moodle 4.1.

Since our upgrade, we seem to be having issues with our memcached servers. We followed the following steps to ensure that our memcache servers are configured correctly: https://docs.moodle.org/401/en/Performance_recommendations#MemCached.

Our memcached settings did work prior to the upgrade to Moodle 4.1.

The link above also linked the following article as to how to configure the memcache servers: https://www.tecmint.com/install-memcached-on-centos-7/. Our servers are configured accordingly.

However, in Moodle under the cache settings (moodleurl/cache/admin.php), the Memcached server option does not have the "green tick" indicating that Moodle is using the memcached servers correctly.

We can see activity on the memcached servers, but it appears as if Moodle is not "aware" of the memcached servers, so we are experiencing caching issues, such as the cache being recreated, causing slow loading times on our site.

Does anyone perhaps have any advice in this regard?

Any feedback would be greatly appreciated.

Kind regards

回复Jaco-Louis Kruger

Re: Moodle 4.1 Memcached issues

Tim Hunt -
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If you are on AWS, then do yourself a favour and switch to redis (or better the Elasticache redis equivalent). There are known issues with Memcache.
回复Jaco-Louis Kruger

Re: Moodle 4.1 Memcached issues

Jaco-Louis Kruger -
Hi everyone

Thank you for the feedback in this regard.

We have followed the advice of @Tim Hunt (posted on this forum), and implemented Redis. Since the implementation of Redis servers, we have been able to use caching in Moodle again.

I am still uncertain as to why exactly memcache stopped working, but Redis has solved the abovementioned issues.

Kind regards
回复Jaco-Louis Kruger

Re: Moodle 4.1 Memcached issues

Susan Mangan -
Just to add to this post should anyone else encounter this - there are at least 2 more of us experiencing issues with memcached after upgrade to 4.1

https://moodle.org/mod/forum/discuss.php?d=450672
回复Susan Mangan

Re: Moodle 4.1 Memcached issues

Howard Miller -
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Again - the simplest "do something" solution is probably to switch to Redis.

Also to note 'memcache' and 'memcached' are different things (with insane naming)
回复Jaco-Louis Kruger

Re: Moodle 4.1 Memcached issues

Jaco-Louis Kruger -
Hi everyone

As the original poster of the thread, I would just like to thank Tim Hunt for the suggestion to switch to redis. We have not encountered any further issues with redis.

Kind regards
Jaco-Louis