BPFTUNE-IP-FRAG(8)

✨ BPFTUNE-IP-FRAG ✨

okay bestie so this is the IP fragmentation plugin for bpftune, living in section 8 of the System Manager's Manual 💅 and it's here to babysit your fragment reassembly memory limits. that's the whole vibe. let's get into it 🫶

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💖 NAME 💖

BPFTUNE-IP-FRAG — the IP fragmentation bpftune plugin that handles fragment reassembly memory limits 👑

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🌸 DESCRIPTION 🌸

So for IPv[46] fragmentation reassembly, your memory is capped at:

net.ipv[46].ip[6]frag_high_thresh

and like… if that value is set too low, fragmentation reassembly can just fail 😭. so the move is: keep an eye on your fragmentation reassembly, and bump that value up when you need to 🫶.

BUT WAIT — do not just start bumping if your assembly failures are correlated with increases in frag_high_thresh. that correlation is lowkey telling you that throwing more memory at the problem does not help 🙈. so while that correlation stays high, you should tune the frag_high_thresh value down instead. periodt 💅

🎀 Tunables 🎀

• net.ipv4.ipfrag_high_thresh — how many bytes get devoted to IPv4 fragmentation reassembly; default is 4MB 💖
• net.ipv6.ip6frag_high_thresh — how many bytes get devoted to IPv6 fragmentation reassembly; default is 4MB 💖

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🦋 SEE ALSO 🦋

• bpf(2)
• bpftune(8)

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and that's a wrap bestie 🎀 this iconic lil page comes to you straight from the System Manager's Manual, tagged BPFTUNE-IP-FRAG(8) — no cap, go forth and tune your frags responsibly 💜🫶✨