Load testing Moodle with JMeter

Being the original server load testing tool, introduced in 1998(!), Apache JMeter has always been the number one load testing resp. performance measuring tool for Moodle. Around the release 2.5, Moodle made the testing process vastly simpler through two built-in scripts, Make test course' and Make JMeter test plan, both under Site administration > Development, augmented by a set of add-ons Moodle performance comparison. This document is about using the aforementioned two built-in scripts.

Warning: Do not run these scripts on a production system! These scripts generate large amounts of artificial data and load the server to its limit and beyond, making it to bloat and become non-responsive. Don't even run them on a separate Moodle instance in the production server: their effect on the DBMS is undocumented.

Make test course

This tool creates test courses that include many users, sections, files and various activities. This is intended to provide a standardized measure for checking the reliability and performance of various system components (such as backup and restore).

Warning: Courses created using this feature can occupy a large amount of database and filesystem space (tens of gigabytes). You will need to delete the courses (and wait for various cleanup runs) to release this space again.

Once you have set the debugging level under Site administration > Development > Debugging to DEVELOPER, visit Site administration > Development > Make test course. You have the choice between XS (~10 KB; create in ~1 second), S (~10 KB, create in ~30 seconds), M (~100 KB, create in ~2 minutes), L (~1 GB, create in ~30 minutes), XL (~10 GB, create in ~2 hours) and XXL (~20 GB, created in ~4 hours).

Size of course	users	sections
XS	1	row 1, cell 3
S	100	row 2, cell 3
M	1,000	row 2, cell 3
L	10,000	row 2, cell 3
XL	100,000	row 2, cell 3
XXL	1,000,000	row 2, cell 3

Sample output:

 Creating course
 Creating [Course name]
 Creating assignments (100): . . . . . . . . . . . . done (12.7s)
 Creating pages (200): . . done (1.5s)
 Creating small files (128): done (0.4s)
 Creating big files (5): . done (1.3s)
 Checking user accounts (1000)
 Creating user accounts (1 - 1000): . . . . . . . . done (8.7s)
 Enrolling users into course (1000): . . . . . . done (5.7s)
 Creating forum (500 posts): . . done (1.7s)
 Course completed (32.2s)

The final Continue will give you a view of the course thus created.

Make JMeter test plan

This tool creates a JMeter test plan file along with the user credentials file. Here too it is necessary to set Site administration > Development > Debugging to DEVELOPER. Also note that, unlike making the test course, this is a single script. To the PHP max_execution_time need to be at least as long as the time for the whole script, which could be anything from a minute to hours depending on the size of the course you select.

This test plan is designed to work along with Moodle performance comparison, which makes easier to run the test plan in a specific Moodle environment, gathers information about the runs and compares the results, so you will need to download it and use it's test_runner.sh script or follow the installation and usage instructions.

You need to set the same password for all the test users by adding the linke $CFG->tool_generator_users_password = 'moodle';' to config.php of Moodle. You might want to set '$CFG->passwordpolicy = 0;' too in case the proposed user password conflicts with the password policy of the site.

There is no default value for this password to prevent unintended usages of the tool. You need to use the update passwords option in case your course users have other passwords or they were generated by tool_generator but without setting a $CFG->tool_generator_users_password value.

It is part of tool_generator so it works well with the courses generated by the courses and the site generators, it can also be used with any course that contains, at least: - Enough enrolled users (depends on the test plan size you select) with the password reset to 'moodle' - A page module instance - A forum module instance with at least one discussion and one reply

You might want to consider your servers capacity when running large test plans as the amount to load generated by JMeter can be specially big. The ramp up period has been adjusted according to the number of threads (users) to reduce this kind of issues but the load is still huge.

Visit Site administration > Development > Make JMeter test plan. Under Size of course your have six possibilities: XS (1 user, 5 loops and 1 rampup period), S (30 users, 5 loops and 6 rampup period), M (100 users, 5 loops and 40 rampup period), L (1000 users, 6 loops and 100 rampup period), XL (5000 users, 6 loops and 500 rampup period) and XXL (1000 users, 7 loops and 800 rampup period). As target course select one of the courses created above. Also Update course users password should be ticked.

Once successful you can download a test plan testplan_timestamp.jmx and a users file users_timestamp.csv

 $ php admin/tool/generator/cli/maketestplan.php --help
 Options:
 -h, --help              Print out this help
 --shortname             Shortname of the test plan's target course (required)
 --size                  Size of the test plan to create XS, S, M, L, XL, or XXL (required)
 --bypasscheck           Bypasses the developer-mode check (be careful!)
 --updateuserspassword   Updates the target course users password according to $CFG->tool_generator_users_password
 
 * XS (1 Nutzter, 5 Schleifen und 1 Steigerungsrate)
 * S (30 Nutzter, 5 Schleifen und 6 Steigerungsrate)
 * M (100 Nutzter, 5 Schleifen und 40 Steigerungsrate)
 * L (1000 Nutzter, 6 Schleifen und 100 Steigerungsrate)
 * XL (5000 Nutzter, 6 Schleifen und 500 Steigerungsrate)
 * XXL (10000 Nutzter, 7 Schleifen und 800 Steigerungsrate)
 
 Consider that, the server resources you will need to run the test plan will be higher as the test plan size is higher.
 
 Example from Moodle root directory: 
 $ sudo -u www-data /usr/bin/php admin/tool/generator/cli/maketestplan.php --shortname="testcourse_12" --size=S

Running the test plan on JMeter

JMeter is a Java application so it can run on Windows, Mac, or Linux. It can be run on the command line on a server but you should also install a graphical user interface version on your desktop. You can check if Java is installed by opening a console and entering: java -version If it doesn't return a version, go to the Java site and install.

To install JMeter go to the JMeter page, download the zip and unzip it to the directory of your choice.

To run JMeter. open the /bin subdirectory and use either jmeter.bat on Windows or ./jmeter on Linux. This will open the JMeter GUI.

First step is to go to File -> Open and select the testplan.jmx file. This will open a tree on the left hand side of JMeter. Open the Warm-up site -> Default site request and enter the protocol (http or https) and Server name or IP. Then go to CSV Users Data and locate your users.csv file under Filename. Repeat this for Moodle Test.

Right mouse click on the Test Plan, then Add -> Listener. I choose Aggregate Report so I can follow the run as it happens. Save the changes in your test plan and run it.

See also

• Apache JMeter homepage
• Jmeter or loading script/app to simulate concurrent users takng quizzes (October 2018)
• Has anyone successfully run a jmeter test with 1000 users? (April 2018)