I'm talking about 100 to 300 users on a daily basis. Below are the specs and the configuration of the server.
Should we get an upgrade or there's something wrong with the configuration? Any help will be appreciated. thanks
Would help to know Moodle version, MySQL version, PHP version.
Run the following query with superuser credentials to DB server:
mysql> show variables like 'max_connections';
and
mysql> show variables like 'innodb_buffer%';
Am willing to bet Bitnami may not have a .sh script that checks DB settings and offers suggestions for tweaking DB server settings so suggest installing MySQLTuner (a perl script) and run it with superuser credentials. It will make recommendations as to needed tweaks.
https://github.com/major/MySQLTuner-perl
See an example of output of tuner ...
https://www.linode.com/docs/guides/how-to-optimize-mysql-performance-using-mysqltuner/
'SoS', Ken
Since you've reported database connections issue ...
The queries are very appropriate:
max_connections is default 151 ... think tuner might tell you it needs to be higher.
Also ... innodb buffer pool size and instances ... am certain Tuner will have something to say about them!
Forgot to ask is this server is an all-in-one .. apache + mysql on same server. If so, tweaks to tuning MySQL's memory needs to fit with what apache is using/configured to use.
So one more command:
free -h
You might also wanna look at 'top' ... the top of top and how mysqld is behaving in list of processes - espeically when server begins to be hit by many students.
'SoS', Ken
1.9 Gig total memory to work with? Wow!
See mysqld 101% of CPU?
@Visvanath - what do you think? That enough to handle very many users?
'SoS', Ken
Hi Ken, Hi Visvanath
TY for your patience, i've restarted the server
Also run up the tuner, below are the recommendations:
-------- Recommendations ---------------------------------------------------------------------------
General recommendations:
Control warning line(s) into /opt/bitnami/mysql/data/mysqld.log file
Control error line(s) into /opt/bitnami/mysql/data/mysqld.log file
MySQL was started within the last 24 hours - recommendations may be inaccurate
Reduce your overall MySQL memory footprint for system stability
Dedicate this server to your database for highest performance.
We will suggest raising the 'join_buffer_size' until JOINs not using indexes are found.
See https://dev.mysql.com/doc/internals/en/join-buffer-size.html
(specially the conclusions at the bottom of the page).
Consider installing Sys schema from https://github.com/mysql/mysql-sys for MySQL
Consider installing Sys schema from https://github.com/FromDual/mariadb-sys for MariaDB
Before changing innodb_log_file_size and/or innodb_log_files_in_group read this: https://bit.ly/2TcGgtU
Variables to adjust:
*** MySQL's maximum memory usage is dangerously high ***
*** Add RAM before increasing MySQL buffer variables ***
join_buffer_size (> 256.0K, or always use indexes with JOINs)
innodb_buffer_pool_size (>= 46.1G) if possible.
innodb_log_file_size should be (=32M) if possible, so InnoDB total log files size equals to 25% of buffer pool size.
Bottom line ... server is underpowered to run your moodle.
Total memory shows 2Gig ... and tuner recommends increasing things that would put your server into a completely unstable state.
this item:
innodb_buffer_pool_size (>= 46.1G) if possible
is not possible ... you only have 2G memory for everything.
So it's time for you to investigate what options you have with service provider ... where you host.
No ... I do not know any work-around and won't even try to suggest any!
'SoS', Ken
