2 ms·
The UDP checksum is optional and weak. It's mostly a waste of time. It's far more likely if you get a bit flip that the layer 1 hardware will just drop the pa
by jandrese 1y ago
The UDP checksum is optional and weak. It's mostly a waste of time.
It's far more likely if you get a bit flip that the layer 1 hardware will just drop the packet because it has a much better checksum that detected the error first. Even if you know every part of the hardware and software stack you have to plan for an occasional packet drop.
- jeroenhd 1y agoMy point wasn't that you should rely on the weak checksum, but rather that the possibility for failure is already baked in even for such a small set of fields, because errors of any kind can happen at any point even in the simplest setups. The statement With adjustments to ring buffers, IRQ/core affinity, and receive buffer size, you can receive a saturated 40GbE stream with no packet loss. _Probably_ works out _most_ of the time in physical setups (especially in server environments with strict ECC memory), but it's not something you can write a protocol around if you need all of that data to _actually_ arrive.