FastWriter implements buffered I/O, which is fast than bufio package and have better P99 performance. Run benchmarks:

go test -bench . -benchmem -benchtime 3s

If you need file rotation function, use lumberjack as the underline writer. Similar library:

• BufferedWriteSyncer

Benchmark result:

$ go test -bench . -benchmem
goos: darwin
goarch: arm64
pkg: github.com/ethanvc/fw
Benchmark_Lumberjack-12                   300721              4065 ns/op               0 B/op          0 allocs/op
Benchmark_FileWriter-12                   418149              2816 ns/op               0 B/op          0 allocs/op
Benchmark_MemoryMapWriter-12             1271971               949.8 ns/op             0 B/op          0 allocs/op
Benchmark_BatchWriter-12                 1272800               943.2 ns/op             0 B/op          0 allocs/op
Benchmark_MultiBufferWriter-12            781482              1769 ns/op              24 B/op          0 allocs/op
Benchmark_FastWriter-12                  1385382               864.9 ns/op             1 B/op          0 allocs/op
Benchmark_NopWriter-12                   1295154               927.8 ns/op             0 B/op          0 allocs/op
Benchmark_BufioWriter-12                 1246978               967.4 ns/op             0 B/op          0 allocs/op
PASS
ok      github.com/ethanvc/fw   14.944s