Cursor.Put: doesn't have bench, but has heap-pointer cgo overhead

[AskAlexSharov]

go test -benchmem -bench=BenchmarkCursor_Set_Sequence -run=BenchmarkCursor_Put_Sequence -benchtime=200ms -count=5 -cpuprofile=cpu.out ./mdbx
go tool pprof -http=:8080 cpu.out

[AskAlexSharov]

I understand what pointer it is: Cursor
we pass c._c pointer to cursor to C. So tx.Put has less CGO overhead than c.Put:

go test -benchmem -bench=BenchmarkCursor_Put_Sequence -run=BenchmarkCursor_Put_Sequence -benchtime=200ms -count=5 -cpuprofile=cput.out ./mdbx
goos: linux
goarch: amd64
pkg: github.com/erigontech/mdbx-go/mdbx
cpu: AMD EPYC 4344P 8-Core Processor
BenchmarkCursor_Put_Sequence-16    	   24308	      9847 ns/op	       0 B/op	       0 allocs/op
BenchmarkCursor_Put_Sequence-16    	   24009	      9956 ns/op	       0 B/op	       0 allocs/op
BenchmarkCursor_Put_Sequence-16    	   24308	      9846 ns/op	       0 B/op	       0 allocs/op
BenchmarkCursor_Put_Sequence-16    	   24084	      9963 ns/op	       0 B/op	       0 allocs/op
BenchmarkCursor_Put_Sequence-16    	   24274	      9924 ns/op	       0 B/op	       0 allocs/op

 go test -benchmem -bench=BenchmarkTxn_Put_Sequence -run=BenchmarkTxn_Put_Sequence -benchtime=200ms -count=5 -cpuprofile=txput.out ./mdbx
goos: linux
goarch: amd64
pkg: github.com/erigontech/mdbx-go/mdbx
cpu: AMD EPYC 4344P 8-Core Processor
BenchmarkTxn_Put_Sequence-16    	   37184	      6314 ns/op	       0 B/op	       0 allocs/op
BenchmarkTxn_Put_Sequence-16    	   38715	      6170 ns/op	       0 B/op	       0 allocs/op
BenchmarkTxn_Put_Sequence-16    	   38653	      6207 ns/op	       0 B/op	       0 allocs/op
BenchmarkTxn_Put_Sequence-16    	   38214	      6274 ns/op	       0 B/op	       0 allocs/op
BenchmarkTxn_Put_Sequence-16    	   38389	      6227 ns/op	       0 B/op	       0 allocs/op
PASS
ok  	github.com/erigontech/mdbx-go/mdbx	1.204s

[AskAlexSharov]

I see some project:
https://github.com/sunvim/gmdbx/blob/main/txn.go#L1597
which using https://github.com/octu0/unsafecgo