tailscale/portlist/portlist_windows.go
Brad Fitzpatrick 120273d7f6 portlist: document, clean up, fix an open fd spike, optimize a bit
I noticed portlist when looking at some profiles and hadn't looked at
the code much before. This is a first pass over it. It allocates a
fair bit. More love remains, but this does a bit:

name       old time/op    new time/op    delta
GetList-8    9.92ms ± 8%    9.64ms ±12%     ~     (p=0.247 n=10+10)

name       old alloc/op   new alloc/op   delta
GetList-8     931kB ± 0%     869kB ± 0%   -6.70%  (p=0.000 n=10+10)

name       old allocs/op  new allocs/op  delta
GetList-8     4.59k ± 0%     3.69k ± 1%  -19.71%  (p=0.000 n=10+10)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2020-03-13 21:06:41 -07:00

19 lines
464 B
Go

// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package portlist
import "time"
// Forking on Windows is insanely expensive, so don't do it too often.
const pollInterval = 5 * time.Second
func listPorts() (List, error) {
return listPortsNetstat("-na")
}
func addProcesses(pl []Port) ([]Port, error) {
return listPortsNetstat("-nab")
}