Introduce variations

For the moment, we only have a single value for the parameter. But we want to have variation. In the current situation, we have a NFS server with 8 processes managing the requests. We want to see how this number of processes influences the performances of the IOR benchmark. We will create two variants:

• fast: with more processes for the NFS server (let us say 32)
• slow: with fewer processes (let us say 2)

We can add the variants in the setup.toml file as follows:

# setup.toml

[project]

[params]
nfsNbProcs=8

[slow.params]
# to select this variant use:
# nxc build --setup slow
nfsNbProcs=2

[fast.params]
# to select this variant use:
# nxc build --setup fast
nfsNbProcs=32

When we build the composition we can pick the variant as:

nxc build --setup fast
# or
nxc build -s slow

If there is no --setup or -s flag, NixOS Compose will take the default values of the parameters.