show how to use gpool.
.
|-- cmd
| |-- client //client main
| | `-- client.go
| `-- server //server main
| `-- server.go
|-- dial
| |-- connection.go //connection item
| `-- dial.go //pool
|-- general.toml //config file
|-- go.mod
`-- go.sum
go build ./cmd/client/
go build ./cmd/server/
./server
# open another terminal
./client