Title: OpenBSD and Linux comparison: data transfer benchmark | |
Author: Solène | |
Date: 14 November 2021 | |
Tags: openbsd networking | |
Description: | |
# Introduction | |
I had a high suspicion about something but today I made measurements. | |
My feeling is that downloading data from OpenBSD use more "upload data" | |
than on other OS | |
I originally thought about this issue when I found that using OpenVPN | |
on OpenBSD was limiting my download speed because I was reaching the | |
upload limit of my DSL line, but it was fine on Linux. From there, | |
I've been thinking since then that OpenBSD was using more out data but | |
I never measured anything before. | |
# Testing protocol | |
Now that I have an OpenBSD router it was easy to make the measures with | |
a match rule and a label. I'll be downloading a specific file from a | |
specific server a few times with each OS, so I'm adding a rule matching | |
this connection. | |
```pf.conf rule | |
match proto tcp from 10.42.42.32 to 145.238.169.11 label benchmark | |
``` | |
Then, I've been downloading this file three times per OS and resetting | |
counter after each download and saved the results from "pfctl -s | |
labels" command. | |
OpenBSD comp70.tgz file from an OpenBSD mirror | |
The variance of each result per OS was very low, I used the average of | |
each columns as the final result per OS. | |
# Raw results | |
```results | |
OS total packets total bytes packets OUT bytes OUT packets I… | |
----- ------------- ----------- ----------- --------- ---------… | |
OpenBSD 175348 158731602 72068 3824812 10328 … | |
OpenBSD 175770 158789838 72486 3877048 10328 … | |
OpenBSD 176286 158853778 72994 3928988 10329 … | |
Linux 154382 157607418 51118 2724628 10326 … | |
Linux 154192 157596714 50928 2713924 10326 … | |
Linux 153990 157584882 50728 2705092 10326 … | |
``` | |
# About the results | |
A quick look will show that OpenBSD sent +42% OUT packets compared to | |
Linux and also +42% OUT bytes, meanwhile the OpenBSD/Linux IN bytes | |
ratio is nearly identical (100.02%). | |
Chart showing the IN and OUT packets of Linux and OpenBSD side by side | |
# Conclusion | |
I'm not sure what to conclude except that now, I'm sure there is | |
something here requiring investigation. |