Joomla websites keep loosing connection to databases (I think)

With the memory issue and the database quits - does this damage the data?

@landed

This is what I thought I’d see:

2017-06-21T15:43:49.711386Z 0 [ERROR] InnoDB: mmap(137428992 bytes) failed; errno 12
2017-06-21T15:43:49.711400Z 0 [ERROR] InnoDB: Cannot allocate memory for the buffer pool

The first error specifically means that MySQL isn’t able to allocate the RAM it needs to continue to function normally, thus it crashes. In this specific scenario, you need to upgrade to at least 1GB of RAM so that MySQL has the RAM it needs to function normally.

@landed

The issue looks to be more so with PHP than it does MySQL, at least from the error in your post. You can check the MySQL error log by running:

tail -25 /var/log/mysql/error.log

If that doesn’t work, you may need to adjust the path depending on the directory that is used by your version of MySQL.

You should be able to do an ls on the /var/log directory to find the correct one.

ls /var/log

From there, we can see if MySQL is actually crashing and if so, what is being logged. If we find that MySQL is crashing, it’s most likely due to limited RAM, in which case I’d recommend upgrading your Droplet to the next size up. So if this is a 512MB Droplet, upgrade to a 1GB Droplet.

Optimizations can be done on smaller Droplets, though it’s constant and on-going. It’d be far easier to upgrade and add free RAM to what’s available unless your comfortable modifying core configuration and troubleshooting.

…

That said, since this is an [error] and not a [warning], it’s something you need to fix. Generally when PHP can’t write to the sessions directory, it either doesn’t exist or you simply don’t have permission to write to it. That seems to be the case here.

If you run:

ls -al /var/lib/php

the ./sessions directory should be owned by root and have default permissions of drwx-wx-wt. If you seen any variance there, then that may very well be the cause.

In most cases, it’s better to actually write session data to another directory, other than the global, if possible. In some cases this can be configured by the script or application, in others, there are no direct options to do so. You’d have to check and see if Joomla supports this. If it does, you could simply create a new directory below your public directory and call it session and change to use that directory. That way you’re in full control over the directory and how it’s handled.

Hi @landed

The default PHP session.save_path is /var/lib/php/sessions, but if somehow the session cleaner script has never been able to run, then this directory might contain an extreme number of files, which means it cannot create new sessions. Run this command ls /var/lib/php/sessions | wc -l to get the current count of files.

I’m not seeing any indication of a database issue, the error seems pretty clear: it’s trying and failing to save php session data at the path specified in the error message. You need to make sure the path in the settings (php settings, not joomla) is correct, and that the filesystem permissions and ownership are also correct.