Hamilton C shell and Cygwin bash date loop windows under Windows 7.

Shows relative performance of Hamilton C shell and Cygwin bash running a popular benchmark. The numbers to the left show how many times per second that particular shell was able to run the date utility. The overall run time for each iteration is split between the shell, the operating system and the date utility. Since the operating system's time to create a process is given and the date utility is expected to be quite fast, this benchmark is intended to measure how fast the shell does its part to create processes. The bigger the number the better.

On this particular benchmark, Cygwin's bash averaged 7.2 processes created per second. Hamilton C shell averaged 88.1 per second, about 12x as fast.

The multithreaded C shell "Really fast date loop" example "cheats" by separating the activities into two threads. One thread runs date as fast as possible (presumably, the same 88 times per second), updating a shared variable. The other thread simply reports the latest value as fast as possible. The resulting numbers (around 125,000 per second) are, of course, a little silly; the C shell isn't really 18,000x as fast. The example is simply a reminder that on Windows, processes are more expensive than on Unix, but threads are very cheap and that if the problem lends itself to a multithreaded solution, improvements can be quite dramatic.

System configuration:

• Standard 2008 aluminum MacBook
• Intel Core 2 Duo @ 2.4GHz
• 4.0GB RAM
• 64-bit Windows 7 Ultimate
• 160GB C: partition, 60% free