In plasma-driven X-ray lasers, it is critical to optimize the duration and time delay between pump pulses. In this study, we have done parametric simulations in order to systematically investigate the optimum time configuration of pump pulses. Here, we are mainly interested in soft X-ray lasers created using a Ar target irradiated with laser pulses, which operate at a wavelength λ = 46.9 nm in the 2p53p1(J = 0) → 2p53s1(J = 1) laser transition. It is shown that the optimum time scale required to achieve Ne-like ions, as well as the time required to generate a population inversion depend on the combined effect of the electron temperature and electron density. The electron density and temperature are respectively a factor of ≈2.1- and ≈5-times higher in the case of a short pulse of 0.1 ps in comparison to a long pulse of 1,000 ps (at a constant fluence). The most effective lasing happens with short pulses with a pulse duration comparable to the total relaxation time from the upper level, namely Δτp ≤ 35 ps. Power laws to predict the optimum laser intensity to achieve Ne-like Ar+8 are obtained.