Frequently Asked Questions

How to speed up the test process?


Beware, when talking about speed a lot of things have to be taken into consideration. Indeed here is a non-exhaustive list of things that fluctuate the testing speed.

  • Bandwidth.
  • DNS Server response time.
  • CPU.
  • ISP’s who blocks a big amount of connection to the outside world.
  • Our databases management (do not apply for PostgreSQL, MySQL and MariaDB format).
  • Amount of data to test.
  • Disk I/O in particular as PyFunceble is heavy on the I/O * RamDrives and NVME disks are very suitable for PyFunceble CSV db.

I have a dedicated server or machine just for PyFunceble

Simply increase the number of maximal workers PyFunceble is allowed to use through the –max-workers argument.

By default, the number of workers is equal to:


meaning that if you have 8 CPU threads, the value will be automatically set to 6.

If that’s not sufficient for you, you may try the dangerous –chancy argument.


Keep in mind that the --max-workers (-w) mostly - if not only - affects the tester processes. Because we want to safely write the files(Disk I/O), we still need a single process that reads the submitted results and generates the outputs.

The reason we added this to PyFunceble 4.0.0 is we don’t want to have a wrongly formatted file output.

Setup and use ramfs

What is a ramfs and why not use tmpfs?

ramfs is better than tmpfs when data needs to be secret, since ramfs data never gets swapped (saved to a physical storage drive), while tmpfs may get swapped. Third parties who later gain root or physical access to the machine then can inspect the swap space and extract sensitive data.

The HOWTO solution

You can prepare ramfs mount so any non-privileged user can mount/unmount it on-demand.

To do this, you will need root privilege, once. Ask the administrator of your system to set this up for you, if you lack root privileges.

At first, you need to add a line to the /etc/fstab. The line in fstab may look like this:

  • /mnt/ramfs is a mount point, where the ramfs filesystem will be mounted. Directory most exist.
  • noauto option prevents this from being mounted automatically (e.g. at system’s boot-up).
  • user makes this mountable by regular users.
  • size sets this “ramdisk’s” size (you can use M and G here)
  • mode is very important, with the octal :code 0770 only root and user, who mounted this filesystem, will be able to read and write to it, not the others (you may use different :code of your choice as well, but be very sure about it!).


We recommend you to set the file mode to 0777 in case you are using this in relation to any kind of scripting, to ensure subprocesses have access to the file(s). In all other cases, you should set the folder permision to 0770.


$ mount /mnt/ramfs/


$ umount /mnt/ramfs/

This chapter has practically been copied from creditted to Neurotransmitter as it is well written and cover our purpose for describing how to setup a ramFS to be used for testing with PyFunceble.

Next, we need to configure PyFunceble to use the newly created and mounted ramFS. This is done with the PYFUNCEBLE_OUTPUT_LOCATION ; now all outputs are stored in the ramFS, so remember to copy the results to a stationary file path when you are done.

Next time you are going to run a test with PyFunceble are will do:
  1. Mount the ramFS
  2. Copy the last test results to the ramFS
  3. Run your test
  4. Copy your results from ramFS to a stationary file path.