We propose a peak-tracking BOTDA (PT-BOTDA) equipped with an efficient dynamic Brillouin frequency shift (BFS) searching scheme based on ternary search. The proposed scheme establishes a feedback loop between the chosen frequency and the corresponding Brillouin gain to reduce the required number of scanning frequencies in one measurement. We also evaluate the performance of the proposed scheme under scenarios of different searching granularities and dynamic sensing ranges. Experimental results indicate that in all situations, the proposed PT-BOTDA can achieve at least 85% reduction in the scanning frequency number with a 3-meter spatial resolution, while maintaining a convincing BFS searching accuracy under sufficient SNR condition.