Use the proper netlink buffer size with large kernel pages #258
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bschwind
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Nice comments, nice fix!
+1 for @strohel's suggestion of not using default features in nix.
On my machine, sysconf is <1ms but is called >200 times when running innernet up <network> given that it's called in a pretty low-level function. I don't think it's a bad idea just from a cleanliness perspective to throw it in a OnceCell, especially since Rust will likely stabilize a similar API in std soon enough.
The recommended netlink buffer size is based on the system's page size, which means that the current size is far too small for systems with 16k or 64k pages, such as Asahi Linux or RHEL's kernel-64k for ARM64. On these systems, the server fails to start with errors like this: Error: Decode error occurred: invalid netlink buffer: length field says 1444 the buffer is 1260 bytes long Instead, follow the kernel's own netlink docs to compute the buffer size. The approach here matches the approach merged into Chromium recently: https://chromium-review.googlesource.com/c/chromium/src/+/4312885
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The recommended netlink buffer size is based on the system's page size, which means that the current size is far too small for systems with 16k or 64k pages, such as Asahi Linux or RHEL's kernel-64k for ARM64. On these systems, the server fails to start with errors like this:
Error: Decode error occurred: invalid netlink buffer: length field says 1444 the buffer is 1260 bytes long
Instead, follow the kernel's own netlink docs to compute the buffer size. The approach here matches the approach merged into Chromium recently:
https://chromium-review.googlesource.com/c/chromium/src/+/4312885