Interesting tests two people ran on tight loops toggling GPIO pins - max frequency performance on GPIO
http://www.savagehomeautomation.com/projects/raspberry-pi-java-gpio-frequency-benchmarks.html
and
http://codeandlife.com/2012/07/03/benchmarking-raspberry-pi-gpio-speed/
- Shell + /proc/mem = 3.4 kHz
- Python + wiringPi = 20 kHz
- Python + RPI.GPIO = 44 kHz
- C + native = 14-22 MHz
- C + BCM 2835 = 4.7 - 5.1 MHz
- C + wiringPi = 6.9 - 7.1 MHz
- Perl + BCM 2835 = 35 kHz
- Java + OpenJDK 7 + ZeroVM = 5 kHz
- Java + OpenJDK 7 + JamVM = 10.75 kHz
- Java + OpenJDK 7 + Avian = Error; untested
- Java + OracleJDK 8 (ea) + HotspotVM = 153 kHz
- Java + OracleJDK 7u10 + HotspotVM = 161 kHz (on soft-float Debian "Wheezy")
