Increase NFS rsize/wsize for netboot tutorial #1796
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rsize and wsize normally default to 1048576 (1MB) for NFS mounts, but for an NFS root device they default to 4096 (4KB). This can lead to a significant performance degradation if the user expects the normal defaults.
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@timg236 Do you know anything about this? I have no idea. |
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I've never tried it |
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@JamesH65 @timg236 rsize and wsize are parameters that govern the negotiated packet size for NFS filesystems. They cap at 1MB (the param is in bytes). With a typical NFS mount on a Pi, this defaults to 1MB. However, the NFSROOT kernel directive has different default values. In the case of the kernel NFSROOT, these parameters default to 4KB which fragments every read/write to the NFS root since each packet will be capped at 4KB rather than a max at 1MB. |
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I think it would be better to put that text in there explaining that to improve performance you can add those options |
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In light of #1911 is this PR still relevant? If there is supporting third-party documentation outside of this repo, and there hasn't been much recent progress I'd be inclined to close it? This feels very much non-Raspberry Pi specific material and therefore outside the scope of the more lightweight documentation set? |
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After some consideration I'm closing. |
rsize and wsize normally default to 1048576 (1MB) for NFS mounts, but for an NFS root device they default to 4096 (4KB). This can lead to a significant performance degradation if the user expects the normal defaults.