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Bpftune uses BPF to auto-tune Linux systems

(github.com)
256 points BSDobelix | 1 comments | 17 Nov 24 11:38 UTC | HN request time: 0.427s | source
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robinhoodexe ◴[17 Nov 24 12:22 UTC] No.42163820[source]▶
Is tuning the TCP buffer size for instance worth it?
replies(6): >>42163899 #>>42166594 #>>42167580 #>>42167891 #>>42168594 #>>42169545 #
viraptor ◴[17 Nov 24 12:41 UTC] No.42163899[source]▶
It depends. At home - probably not. On a fleet of 2000 machines where you want to keep network utilisation close to 100% with maximal throughput, and the non-optional settings translate to a not-trivial value in $ - yes.
replies(1): >>42164286 #
londons_explore ◴[17 Nov 24 14:17 UTC] No.42164286[source]▶
TCP parameters are a classic example of where an autotuner might bite you in the ass...

Imagine your tuner keeps making the congestion control more aggressive, filling network links up to 99.99% to get more data through...

But then any other users of the network see super high latency and packet loss and fail because the tuner isn't aware of anything it isn't specifically measuring - and it's just been told to make this one application run as fast as possible.

replies(1): >>42167701 #
1. withinboredom ◴[17 Nov 24 22:00 UTC] No.42167701[source]▶
It literally covers this exact scenario in the readme and explains how it prevents that.