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lucypa / sDDF

seL4 Device Driver Framework
BSD 2-Clause "Simplified" License
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Performance comparison with Linux XDP #1

Closed ramenhost closed 3 months ago

ramenhost commented 2 years ago

Slide 17 from the seL4 2022 summit here shows performance comparison against the Linux network stack.
[suggestion] It would be great to have a similar comparison against Linux's eBPF based eXpress Data Path (XDP). XDP based user-space stack seems to be more comparable to sDDF by design than the Linux kernel stack.

Indanz commented 1 year ago

I think one reason why the Linux performance is so bad is because Linux's fec drivers maps the DMA buffers uncached, while Lucy maps it cacheable and does manual cache maintenance. If XDP is still using the same fec driver, it still won't be a fair comparison, because it will still be using the crappy imx fec driver.

ramenhost commented 1 year ago

The kernel to user-space memory copy might incur more overhead than cache misses, whereas XDP provides zero-copy data path. That's why wanted to see the performance comparision.