Delete method connection.isAlive() that are no longer in use.

Author: linfeip

x/mongo/driver/topology/connection.go

@@ -14,7 +14,6 @@ import (
 	"fmt"
 	"io"
 	"net"
-	"os"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -526,48 +525,6 @@ func (c *connection) closed() bool {
 	return atomic.LoadInt64(&c.state) == connDisconnected
 }
 
-// isAlive returns true if the connection is alive and ready to be used for an
-// operation.
-//
-// Note that the liveness check can be slow (at least 1ms), so isAlive only
-// checks the liveness of the connection if it's been idle for at least 10
-// seconds. For frequently in-use connections, a network error during an
-// operation will be the first indication of a dead connection.
-func (c *connection) isAlive() bool {
-	if c.nc == nil {
-		return false
-	}
-
-	// If the connection has been idle for less than 10 seconds, skip the
-	// liveness check.
-	//
-	// The 10-seconds idle bypass is based on the liveness check implementation
-	// in the Python Driver. That implementation uses 1 second as the idle
-	// threshold, but we chose to be more conservative in the Go Driver because
-	// this is new behavior with unknown side-effects. See
-	// https://github.com/mongodb/mongo-python-driver/blob/e6b95f65953e01e435004af069a6976473eaf841/pymongo/synchronous/pool.py#L983-L985
-	idleStart, ok := c.idleStart.Load().(time.Time)
-	if !ok || idleStart.Add(10*time.Second).After(time.Now()) {
-		return true
-	}
-
-	// Set a 1ms read deadline and attempt to read 1 byte from the connection.
-	// Expect it to block for 1ms then return a deadline exceeded error. If it
-	// returns any other error, the connection is not usable, so return false.
-	// If it doesn't return an error and actually reads data, the connection is
-	// also not usable, so return false.
-	//
-	// Note that we don't need to un-set the read deadline because the "read"
-	// and "write" methods always reset the deadlines.
-	err := c.nc.SetReadDeadline(time.Now().Add(1 * time.Millisecond))
-	if err != nil {
-		return false
-	}
-	var b [1]byte
-	_, err = c.nc.Read(b[:])
-	return errors.Is(err, os.ErrDeadlineExceeded)
-}
-
 func (c *connection) idleTimeoutExpired() bool {
 	if c.idleTimeout == 0 {
 		return false