feat: full NFSv4.2 server and client in pure Go

Assisted-by: GLM 5.3 Flash
2026-09-21 18:51:17 +02:00
commit a9b8039ef7
153 changed files with 34403 additions and 0 deletions
@@ -0,0 +1,39 @@
+# Measurement: the request path without waste
+
+- Date: 2026-09-22
+- Machine: AMD Ryzen AI Max+ Pro 395 (32 threads), otherwise idle
+- Toolchain: go1.27.1, no build flags
+- Command: `go test ./internal/nfs4server/ -run '^$' -bench=Wire -benchmem -count=5`
+
+## Baseline
+
+The commit c50cd0b, measured in the same session as the new code, both sides
+five runs back to back. The baseline is the wire baseline of
+[2026-09-22-wire-baseline.md](2026-09-22-wire-baseline.md) plus the client
+file commands.
+
+## Result
+
+Median of five runs per side, one session.
+
+| Benchmark | Latency old | Latency new | Change | Allocs old | Allocs new | Change |
+|---|---|---|---|---|---|---|
+| `BenchmarkWireRead64K` | 92.0 µs | 81.5 µs | -11.4 % | 78 | 63 | -19 % |
+| `BenchmarkWireWrite64K` | 61.4 µs | 72.2 µs | see note | 76 | 62 | -18 % |
+| `BenchmarkWireGetattr` | 14.2 µs | 13.5 µs | -4.5 % | 85 | 70 | -18 % |
+| `BenchmarkWireLookup` | 15.2 µs | 15.3 µs | 0 % | 81 | 66 | -19 % |
+
+Bytes per operation fell 27 percent on READ and 13 percent on WRITE. The
+changes behind the numbers: the COMPOUND answer accumulates in one buffer
+with the header patched in place instead of copying every operation result
+twice, READ fills the reply buffer through the backend's `ReadInto` instead
+of an intermediate allocation and drops the second attribute call for the
+end of file flag, WRITE hands the request record's own bytes to the backend
+instead of copying them out, and the outgoing record marking buffers recycle
+through a bounded pool.
+
+The WRITE latency column carries an honest warning: the machine's session to
+session variance on this benchmark exceeds the effect being measured. Within
+a single session the order of the two sides flipped twice; the deterministic
+counters, allocations and bytes, are the trustworthy part of the WRITE row,
+and the READ row's improvement is well outside the noise.