MySQL server has gone away

rainmotorsports

Well-known member
What is the hosting? If it's a VPS from Digital Ocean you need to enable swap. By default they don't have a swap partition and the MySQL server will crash when the ram runs out.
 

Brogan

XenForo moderator
Staff member
Normally I would say that is due to one of these settings:
Code:
wait_timeout
max_allowed_packet
However, you've already changed those.

It could be due to a memory limitation (although swap space should be available - but it may not be).
You may need to monitor the server processes to see exactly what's happening when the install routing is running.

The server error log shows a lot of stuff related to MySQL being killed, but not necessarily why.
 

Matt C.

Well-known member
Normally I would say that is due to one of these settings:
Code:
wait_timeout
max_allowed_packet
However, you've already changed those.

It could be due to a memory limitation (although swap space should be available - but it may not be).
You may need to monitor the server processes to see exactly what's happening when the install routing is running.

The server error log shows a lot of stuff related to MySQL being killed, but not necessarily why.
Thank you, I investigated these and during my investigation, I discovered that the reason is because my ram/CPU usage is too low: 512MB ram. When I was installing addon, the CPU usage clocked out, which resulted in the MYSQL server crashing. I've upgraded my server to 1 GB ram, which fixed the problem.

Thanks to everyone for their help, especially since it turned out to be something so simple. :)
 

Tracy Perry

Well-known member
Thank you, I investigated these and during my investigation, I discovered that the reason is because my ram/CPU usage is too low: 512MB ram. When I was installing addon, the CPU usage clocked out, which resulted in the MYSQL server crashing. I've upgraded my server to 1 GB ram, which fixed the problem.

Thanks to everyone for their help, especially since it turned out to be something so simple. :)
Suggestion... NEVER get a 512mb VPS. That's not going to be NEAR enough unless you are VERY good at optimizing a system. Minimum is 1GB and honestly, 2GB is better.
 

rainmotorsports

Well-known member
Suggestion... NEVER get a 512mb VPS. That's not going to be NEAR enough unless you are VERY good at optimizing a system. Minimum is 1GB and honestly, 2GB is better.
2GB is still going to be an issue if there is no swap. He is just increasing the MTBF until he has enough ram for the system to never swap.

An optimized setup from my testing can run Xenforo for 250 users per second at 512 MB of ram. She starts to suffer a little past the 200 mark but for example TBG runs on 2 GB of RAM and we probably have a peak of 100 users simultaneously. We don't need it but when we do it's there.
 

Tracy Perry

Well-known member
2GB is still going to be an issue if there is no swap. He is just increasing the MTBF until he has enough ram for the system to never swap.

An optimized setup from my testing can run Xenforo for 250 users per second at 512 MB of ram. She starts to suffer a little past the 200 mark but for example TBG runs on 2 GB of RAM and we probably have a peak of 100 users simultaneously. We don't need it but when we do it's there.
Agreed... but even with swap a 512mb setup is WAY to small, ergo my comment about a 1gb minimum and 2gb being better. One assumes that someone setting up a VPS is already familiar with the standard process (of which assigning swap space is a normal part).
 
Last edited:

Anthony Parsons

Well-known member
Yer, I set mine to Centos swap specs, 2 x RAM for first 2GB RAM, then 1 to 1 after that. I actually stumbled upon this issue last year setting up a 512MB RAM system for some testing. I like that Linode changed their RAM so even the smallest system uses 1GB for $5 monthly.
 
Top