 However, Jochen Liedtke showed that Mach's performance problems were the result of poor design and implementation, specifically Mach's excessive cache footprint.Liedtke demonstrated with his own L4 microkernel that through careful design and implementation, and especially by following the minimality principle, IPC costs could be reduced by more than an order of magnitude compared to Mach.L4's IPC performance is still unbeaten across a range of architectures.