CUBISM-MPCF is a high throughput software for two-phase flow simulations that has demonstrated unprecedented performance in terms of floating point operations, memory traffic and storage. The software has been optimized to take advantage of the features of the IBM BlueGene/Q (BGQ) platform to simulate cavitation collapse dynamics using up to 13 Trillion computational elements. The performance of the software has been shown to reach an unprecedented 14.4 PFLOP/s on 1.6 Million cores corresponding to 72% of the peak on the 20 PFLOP/s Sequoia supercomputer. It is important to note that, to the best of our knowledge, no flow simulations have ever been reported exceeding 1 Trillion elements and reaching more than 1 PFLOP/s or more than 15% of peak. In this work, we first extend CUBISM-MPCF with a more accurate numerical flux and then summarize and evaluate the most important software optimization techniques that allowed us to reach 72% of the theoretical peak performance on BGQ systems. Finally, we show recent simulation results from cloud cavitation comprising 50000 vapor bubbles.