XF 2.2 The table ‘xf_session_activity’ is full

[bburton]

What might cause the xf_session_activity table to become repeatedly full resulting in the contents of forum pages not loading and an error message displaying instead?

The 'hourly clean up' cron job is running, so that's not the reason. This is occurring between those hourly clean ups - about every 20 minutes or so. Running the 'hourly clean up' manually temporarily 'fixes' the problem, then 20 minutes or so later the xf_session_activity table fills up again and this error occurs repeatedly:

XF\Db\Exception: MySQL query error [1114]: The table 'xf_session_activity' is full
src/XF/Db/AbstractStatement.php:230

There is not an unusual number of logged in users. Nothing appears unusual with the number of logged in registered users.

Thanks,

 

[ekool]

Never had that error... even on large sites. Very strange.

I see it's happened to other people before though: https://xenforo.com/community/threads/xf_session_activity-is-full.172623/

 

[bburton]

I found several threads on this same issue, but no explanations

Question: Can unregistered guest activity fill up this xf_session_activity table?

 

[Jja]

What might cause the xf_session_activity table to become repeatedly full resulting in the contents of forum pages not loading and an error message displaying instead?

Not properly configured (tuned) server for given application/traffic.

I would rather ask "how full is full?"
Whats the setup of actual mysql config + available resources ?

Question: Can unregistered guest activity fill up this xf_session_activity table?

Thats exactly what this table contains.

 

[bburton]

XenForo has been running just fine for months (years) with no issues. Nothing recently has been done to change the configuration

I thought xf_session_activity table just kept track of logged in registered users (?)

 

[Jja]

Doesnt change the fact.
Guests, bots also uses sessions and are stored in the table as well.

 

[bburton]

Then its very easy to disable a XenForo forum simply by filling up this little table, no?

 

[Jja]

Its not the Xenforo problem itself but server configuration.

 

[bburton]

Here's an entry from the server error log:

Server error log

• XF\Db\Exception: MySQL query error [1114]: The table 'xf_session_activity' is full
• src/XF/Db/AbstractStatement.php:230
• Generated by: Unknown account
• Jan 9, 2025 at 11:08 PM

Stack trace​

-- XFDB=noForceAllWrite
INSERT IGNORE INTO xf_session_activity (
ip,
controller_name,
controller_action,
view_state,
params,
view_date,
robot_key,
user_id,
unique_key
) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)

------------

 

[cyberdyne]

I also encountered the same problem on a large installation with 20M posts, increased the max_heap_table_size variable several times, but it did not help for long.
Then I looked at the access logs, and realized that these are AI bots from Alibaba Cloud and other similar ones learning and reading content (I had ~40 requests per second) and I just simply blocked the Alibaba autonomous system and a couple of data centers like OVH on nginx) and it helped. Welcome to the age of ai technologies.

After a while I found a topic:

S

Thread 'Learnings: Identifying and getting rid of unwanted traffic'

Apr 6, 2025

I've recently spent some time getting rid of unwanted traffic on my forums and thought maybe the learnings might have value for someone else, so I am writing them up. This is not intended as a tutorial or even advice - it is just a couple of finding that you may find useful or not. Also, there are many ways to Rome, depending from your situation, needs and abilities. So take it with a grain of salt.

Important race conditions for my actions: My forum is pretty small (currently ~2.000 registered users), runs on shared hosting (which limits my possibilities in terms of configuration), I...

• smallwheels
• Replies: 26
• Forum: Forum management

•