librespeed / librespeed/speedtest-cli
CLI results 2x higher RTT
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Description
Hi,
I've noticed that CLI result 2x higher RTT than web speed test.
Here's my web speed test result:
https://librespeed.org/results/?id=17vfzh3

I performed a speed test using cli, strangely, it shows 2x higher RTT than web test.
% librespeed-cli --server 6
Retrieving LibreSpeed.org server list
Selected server: Nuremberg, Germany (1) (Hetzner) [de1.backend.librespeed.org]
Sponsored by: Snopyta @ https://snopyta.org
You're testing from: 2405:6586:2280:1200::dead:beef - Asahi Net, JP (9080 km)
Ping: 535 ms Jitter: 0 ms
Download rate: 5.82 Mbps
Upload rate: 2.22 Mbps
I also measured RTT using ping, the result is same as the web test.
% ping6 de1.backend.librespeed.org
PING6(56=40+8+8 bytes) 2405:6586:2280:1200::dead:beef --> 2a01:4f8:1c1c:93d6::1
16 bytes from 2a01:4f8:1c1c:93d6::1, icmp_seq=0 hlim=35 time=268.486 ms
16 bytes from 2a01:4f8:1c1c:93d6::1, icmp_seq=1 hlim=35 time=266.626 ms
16 bytes from 2a01:4f8:1c1c:93d6::1, icmp_seq=2 hlim=35 time=264.742 ms
16 bytes from 2a01:4f8:1c1c:93d6::1, icmp_seq=3 hlim=35 time=264.809 ms
I haven't dig up the code but I guess you forgot to divide some value by 2.
Best Regards,
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Research direction
Reproduce the issue with librespeed-cli --server 6 and compare its RTT with ping6 de1.backend.librespeed.org. Then inspect the CLI's RTT calculation and verify that the reported value matches the web test and ping result when the bug is fixed.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- go
- Domain
- cli, networking
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100