Mean absolute fractional error (averaged over 200 logarithmically spaced k∈[9×10⁻³, 9] h Mpc⁻¹) with respect to CLASS against run time for various linear power spectrum emulators at four cosmologies and redshift 0. Some emulators are tested on both CPU (left panel) and GPU (right panel). The different colors refer to the emulator used, whereas each cosmology (defined in Sect. 7.1) is denoted by a different symbol.