Use copy file range from sysx

Use pooled buffers for copy

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)

fs/copy.go

@@ -4,10 +4,19 @@ import (
 	"io/ioutil"
 	"os"
 	"path/filepath"
+	"sync"
 
 	"github.com/pkg/errors"
 )
 
+var (
+	bufferPool = &sync.Pool{
+		New: func() interface{} {
+			return make([]byte, 32*1024)
+		},
+	}
+)
+
 // CopyDirectory copies the directory from src to dst.
 // Most efficient copy of files is attempted.
 func CopyDirectory(dst, src string) error {