Impact of Pointers vs Values on CPU
The structure tested contains 20 fields ( int64 )
go test -bench=.
| Benchmarks on Exported | # of op. | dur. per op. |
|---|---|---|
| BenchmarkNewValue-8 | 100000000 | 10.8 ns/op |
| BenchmarkNewPointer-8 | 300000000 | 5.33 ns/op |
| BenchmarkFuncValue-8 | 300000000 | 4.88 ns/op |
| BenchmarkFuncPointer-8 | 2000000000 | 0.38 ns/op |
| BenchmarkMethodValue-8 | 300000000 | 4.87 ns/op |
| BenchmarkMethodPointer-8 | 2000000000 | 0.30 ns/op |
| BenchmarkFuncValueNoRef-8 | 2000000000 | 0.30 ns/op |
| BenchmarkFuncPointerNoRef-8 | 2000000000 | 0.30 ns/op |
| BenchmarkMethodValueNoRef-8 | 2000000000 | 0.30 ns/op |
| BenchmarkMethodPointerNoRef-8 | 2000000000 | 0.30 ns/op |
Just to be sure, let's run the same tests with unexported structs and functions :
| Benchmarks on Unexported | # of op. | dur. per op. |
|---|---|---|
| BenchmarkUnexportedNewValue-8 | 100000000 | 10.7 ns/op |
| BenchmarkUnexportedNewPointer-8 | 300000000 | 5.32 ns/op |
| BenchmarkUnexportedFuncValue-8 | 300000000 | 4.77 ns/op |
| BenchmarkUnexportedFuncPointer-8 | 2000000000 | 0.30 ns/op |
| BenchmarkUnexportedMethodValue-8 | 300000000 | 4.75 ns/op |
| BenchmarkUnexportedMethodPointer-8 | 2000000000 | 0.30 ns/op |
| BenchmarkUnexportedFuncValueNoRef-8 | 2000000000 | 0.30 ns/op |
| BenchmarkUnexportedFuncPointerNoRef-8 | 2000000000 | 0.30 ns/op |
| BenchmarkUnexportedMethodValueNoRef-8 | 2000000000 | 0.30 ns/op |
| BenchmarkUnexportedMethodPointerNoRef-8 | 2000000000 | 0.37 ns/op |