The performance is measured with LinPack which mostly does FP operations and is optimized to run on the architecture, when normal programs are run, it is tough

The performance is measured with LinPack which mostly does FP operations and is optimized to run on the architecture, when normal programs are run, it is tough to run them at full utilization, this is because, a lot of time might be spent in data transfer or I/O apart from the computation ... there would be various other factors !