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13707 :: Just benchmarked NimPacket vs Scapy on Windows

• 0x57Origin (orginal) [2026-02-10T03:38:30+01:00] view original

  NimPacket is really fast

  TCP, UDP, ICMP, DNS, ARP crafting: 50x–290x faster.

  Packet parsing: 15x–20x faster.

  Import time: 5 ms vs 383 ms.

  Memory usage for 50k packets: 1 KB vs 1.1 MB.

  Scapy only wins on raw checksum and IP conversion.

  Everything else goes to NimPacket.

  This is what native Nim + Python bindings can do.

  More updates soon.

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• ITwrx (orginal) [2026-02-10T05:29:15+01:00] view original

  You might consider posting nimpacket-related updates in the nimpacket thread, instead of creating new threads for every update, which could be seen as spammy. It will move that thread to the top anyway, when you do that, since it sorts by latest activity.

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• 0x57Origin (orginal) [2026-02-10T05:34:15+01:00] view original

  Thanks for telling me that i did not know that exists honestly !!!!!!!!!

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• elcritch (orginal) [2026-02-10T09:23:29+01:00] view original

  Scapy only wins on raw checksum and IP conversion.

  Sounds like a place to try out some SIMD! ;)

  There’s a new auto SIMD library: https://github.com/xTrayambak/overdrive or the classic NIMSIMD: https://github.com/guzba/nimsimd

  With the latter I just had an LLM bake up code and test against the scalar code.

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• 0x57Origin (orginal) [2026-02-10T22:15:13+01:00] view original

  I’m not super familiar with SIMD yet, but I’ll definitely look into it. Right now my main focus is stabilizing the NimPacket API and getting solid PCAP support in place. If you or anyone else has suggestions on API design or PCAP features that actually matter in practice, I’d really appreciate the input.

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