All-optical flip-flops based on vertical-cavity surface-emitting lasers (VCSEL) have the potential for a wide range of applications in all-optical signal processing. However, the relationship between the switching time and internal parameters of the laser has not yet been fully understood. To fill this research gap, this paper presents a systematic numerical simulation study on the polarization switching behavior of VCSEL induced by polarization optical injection with the a spin-flip model. The simulation analysis explores the influence mechanism of the internal parameters of the laser on the switching time of the all-optical flip-flop in depth. Based on this, the key parameters, namely the spin flip-flop rate and field decay rate, are further optimized to reduce the switching time and increase the flip-flop repetition frequency. Through parameter optimization, an all-optical flip-flop operation with a high repetition frequency can be achieved. Additionally, by introducing injection detuning and combining it with appropriate injection intensities, the repetition frequency of the all-optical flip-flops can be further improved.