I have 2 raspberry pi's that I wanted to benchmark for load balancing purpose.
- Raspberry pi Model B v1.1 - running Raspbian Jessie
- Raspberry pi Model B+ v1.2 - running Raspbian Jessie
I installed sysbench on both systems and ran: sysbench --num-threads=1 --test=cpu --cpu-max-prime=10000 --validate run on the first and changed --num-threads=4 on the second, as its quadcore and ran both.
The results are not at all what I expected (I obviously expected the multithreaded benchmark to severely outperform the single threaded benchmark). When I ran a the command with a single thread, performance was about the same on both systems. But when I changed the number of threads to 4 on the second Pi it still took the same amount of time, except that the per request statistics showed that the average request took about 4 times as much time. I can seem to grasp why this is.
Here are the results:
Raspberry pi v1.1
Single thread
Maximum prime number checked in CPU test: 20000
Test execution summary:
- total time: 1325.0229s
- total number of events: 10000
- total time taken by event execution: 1324.9665
per-request statistics:
- min: 131.00ms
- avg: 132.50ms
- max: 171.58ms
approx. 95 percentile: 137.39ms
Threads fairness: events (avg/stddev): 10000.0000/0.00 execution time (avg/stddev): 1324.9665/0.00
Raspberry pi v1.2
Four threads
Maximum prime number checked in CPU test: 20000
Test execution summary:
- total time: 1321.0618s
- total number of events: 10000
- total time taken by event execution: 5283.8876
per-request statistics:
- min: 486.45ms
- avg: 528.39ms
- max: 591.60ms
approx. 95 percentile: 553.98ms
Threads fairness: events (avg/stddev): 2500.0000/0.00 execution time (avg/stddev): 1320.9719/0.03
