Zero log becomes slow with file-writer

[raj-prince]

Tried comparing zerolog, zaplog and slog with log destination as file. Although with io.Discard, zerolog is blazing fast, but when we pass a file-writer then zerolog starts performing worst in comparison with zaplog and slog.

Do we know why? Am I missing something?

Here, is the benchmarking number:

// goos: linux
// goarch: amd64
// pkg: go-core/experiment
// cpu: INTEL(R) XEON(R) PLATINUM 8581C CPU @ 2.30GHz
// BenchmarkSlog-192             	  317107	      3560 ns/op	     375 B/op	       9 allocs/op
// BenchmarkSlogAsync-192        	  370838	      2987 ns/op	     722 B/op	      11 allocs/op
// BenchmarkZerolog-192          	  306411	      3858 ns/op	      81 B/op	       3 allocs/op
// BenchmarkZerologAsync-192     	  597055	      2221 ns/op	     369 B/op	       5 allocs/op
// BenchmarkZap-192              	  233199	      4719 ns/op	     477 B/op	       5 allocs/op
// BenchmarkZapAsync-192         	  484533	      2331 ns/op	     756 B/op	       7 allocs/op
// PASS
// ok  	go-core/experiment	8.660s

The complete benchmarking script: https://github.com/raj-prince/go-core/blob/0b96e8124c11d04b0b08f9ef93ec012cb87556c3/experiment/logging_benchmark_test.go#L278

[rs]

Use a diode to decouple events from IO or add buffering. Zerolog does not add anything between events and the writer by default. It is on you to deal with that depending on what makes sense for you application.