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Benchmarking

Photo by Alex manlyx on Unsplash

Time to get the hands dirty and do some benchmarking. The goal of Lab6 is to run the different sound volume algorithms described in my last post in the five different machines and compare them.
I talked about the algorithm in the last post, so now it’s time to talk about the machines. Here they are:


AARCHIE
BBETTY
CCHARLIE
ISRAEL
XERXES
OS
Fedora 28
Fedora 31
Fedora 30
Ubuntu 19.04
Fedora 30
Architecture
aarch64
aarch64
aarch64
aarch64
x86_64
CPU(s)
24
8
8
16
8
Thread(s) per core
1
1
1
1
2
Model name
Cortex-A53
Cortex-A57
X-Gene
Cortex-A72
Intel(R) Xeon(R) CPU E5-1630 v4 @ 3.70GHz
L1d cache
32K
-
unknown
32K
32K
L1i cache
32K
-
unknown
48K
32K
L2 cache
256K
-
unknown
1024K
256K
L3 cache
4096K
-
-
-
10240K

Before running anything, we need to make sure to get the time consumed by the algorithm only. So, I’ve to change the code provided to get the initial and final dates at the right time, do the elapsed time math and display it. Here is an example.


To get more accurate data possible, I choose to run each one 100 times. I also put a delay of 5 minutes between executions. Then I set to run around 10 pm to collect the data in the next morning. With the data, I extracted the average elapsed time, along with the fastest and slowest. Here is my script to do the hard work for me.



Here are the results (numbers in milliseconds):



AARCHIE
BBETTY
CCHARLIE
ISRAEL
XERXES
Multiplication Method
Min
7571.00
933.00
1715.00
1455.00
340.00
Max
11548.00
942.00
1722.00
1456.00
394.00
Avg
7622.43
934.68
1716.26
1455.53
353.02
Lookup Table Method
Min
12732.00
1376.00
2220.00
2558.00
268.00
Max
34445.00
1390.00
2574.00
2591.00
348.00
Avg
13083.50
1379.64
2406.17
2572.67
281.33
Binary Math Method
Min
4079.00
782.00
1231.00
503.00
211.00
Max
4442.00
795.00
1237.00
505.00
254.00
Avg
4101.68
782.91
1232.35
503.02
218.30

We can see a difference between the algorithms. The binary math method is faster on all platforms. The surprise here is that the multiplication method performs better in aarch64 than in x86_64. And the lookup the opposite, performing better in the x86_64 than in the aarch64. However, we can't compare between machines due to incompatibility. See you!
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