FOG Web GUI speed and default storage activity

[JGallo]

Another observation is that upon the sudo service mysql restart on the fog server, the error goes away for DefaultMember in the dashboard. I tried the same thing on other storage nodes but the message is still in the dashboard. Maybe this could be something with remote connections with the mysql database.

[JGallo]

@Wayne-Workman

@Sebastian-Roth remoted in and looks like mysql was limited to 150 connections. He raised it to 250 and now it would appear fixed so far. I’m keeping an eye on the max used connections and it hasn’t gone over 161 so I must have been hitting that 150 max. Thanks for all your help here. Greatly appreciate it.

[Sebastian Roth]

Turns out mysql hit the max connection limit. Not sure what the default limit is but on this system it was 151 concurrent connections. Check for connections numbers are just an example - where much higher on the actual system):

mysql> show status like '%onn%';
+----------------------------------+-------+
| Variable_name                    | Value |
+----------------------------------+-------+
| Aborted_connects                 | 0     | 
| Connections                      | 8     | 
| Max_used_connections             | 4     | 
| Connection_error_max_connections | 1421  |
| Ssl_client_connects              | 0     | 
| Ssl_connect_renegotiates         | 0     | 
| Ssl_finished_connects            | 0     | 
| Threads_connected                | 4     | 
+----------------------------------+-------+

See that Connection_error_max_connections count. So we checked the max_connections setting and increased it:

mysql> show variables like 'max_connections';
+-----------------+-------+
| Variable_name   | Value |
+-----------------+-------+
| max_connections | 151   |
+-----------------+-------+
mysql> set global max_connections = 250;

The change takes effect without restarting the server or mysql!

[JGallo]

@sebastian-roth

I did a git pull and updated FOG to address a Windows 10 issue and upon the update the issue I had with database connections returned. It would appear that mysql goes back to default max connections of 151 after the update. Does the fog installer/updater have mysql update settings? If it does, could I suggest an increase on that max connection limit be part of the fog installer/updater? Or is this something that needs to be manually entered in mysql with the amount of storage nodes and groups I have which was done already to address my issue. Thank you again for your help on this.

[Wayne Workman]

@jgallo said in FOG Web GUI speed and default storage activity:

It would appear that mysql goes back to default max connections of 151 after the update.

Because the setting was only changed in the MySQL config live. The setting has to be set in the mysql configuration file using the process outlined here: https://wiki.fogproject.org/wiki/index.php?title=Troubleshoot_MySQL#Increase_maximum_simultaneous_MySQL_connections

[JGallo]

@wayne-workman

I’m following the steps in Wiki but mysql is on Ubuntu 16.04.3 LTS and when I go to /etc/mysql/my.cnf and try to add the increase of max connections, it errors out. Modifying the mysqld.cnf in /etc/mysql/mysql.conf.d and removing the comment on the line with max connections works. However it’s really odd that when you restart mysql and go into mysql to check the max connections it would show a smaller value then defined in the mysqld.cnf file. Am I right to modify the mysqld.cnf? I’m lost at this but I know that at least the value is increased so it works as intended but with the incorrect value I defined.

[Wayne Workman]

@jgallo I’ll have to look into it, but mysql and mariadb have configuration files where this setting can be used - and when you restart mysql/mariadb it should use the setting and work.

[Sebastian Roth]

@JGallo @Wayne-Workman Just found this on stackexchange. Though it doesn’t say so anywhere in the mysql manual it’s possible that mysql does somehow restrict the max_connections when it’s higher than some internal memory calculations. Maybe give the mysql mem calc a try. On the other hand setting the value up to 250 in the live DB worked like a charm.

[Wayne Workman]

@sebastian-roth said in FOG Web GUI speed and default storage activity:

On the other hand setting the value up to 250 in the live DB worked like a charm.

Sure it works, but it’s not a permanent solution. The changes are undone upon reboot or mysql service restarting.

[JGallo]

@wayne-workman

Very true but making the change in the live DB is a great plan B until a long term plan A is found. I checked the mysql mem calc link and I compared the mysqld.cnf settings for those calculations but many of those variables are not there. I think at this point it works and I don’t foresee needing many more storage nodes in the future for this fog server. I’m happy it’s working now. Thank you both for all your help.