Commit Graph

23 Commits (033bd94d4ca811de4243aca17b6670e95c503807)

Author SHA1 Message Date
Brad Fitzpatrick db2cc393af util/dirwalk, metrics, portlist: add new package for fast directory walking
This is similar to the golang.org/x/tools/internal/fastwalk I'd
previously written but not recursive and using mem.RO.

The metrics package already had some Linux-specific directory reading
code in it. Move that out to a new general package that can be reused
by portlist too, which helps its scanning of all /proc files:

    name                old time/op    new time/op    delta
    FindProcessNames-8    2.79ms ± 6%    2.45ms ± 7%  -12.11%  (p=0.000 n=10+10)

    name                old alloc/op   new alloc/op   delta
    FindProcessNames-8    62.9kB ± 0%    33.5kB ± 0%  -46.76%  (p=0.000 n=9+10)

    name                old allocs/op  new allocs/op  delta
    FindProcessNames-8     2.25k ± 0%     0.38k ± 0%  -82.98%  (p=0.000 n=9+10)

Change-Id: I75db393032c328f12d95c39f71c9742c375f207a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 21ef7e5c35 portlist: add macOS osImpl, finish migration to new style
Previously:

* 036f70b7b4 for linux
* 35bee36549 for windows

This does macOS.

And removes all the compat code for the old style. (e.g. iOS, js are
no longer mentioned; all platforms without implementations just
default to not doing anything)

One possible regression is that platforms without explicit
implementations previously tried to do the "netstat -na" style to get
open ports (but not process names). Maybe that worked on FreeBSD and
OpenBSD previously, but nobody ever really tested it. And it was kinda
useless without associated process names. So better off removing those
for now until they get a good implementation.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 036f70b7b4 portlist: refactor, introduce OS-specific types
Add an osImpl interface that can be stateful and thus more efficient
between calls. It will later be implemented by all OSes but for now
this change only adds a Linux implementation.

Remove Port.inode. It was only used by Linux and moves into its osImpl.

Don't reopen /proc/net/* files on each run. Turns out you can just
keep then open and seek to the beginning and reread and the contents
are fresh.

    name                    old time/op    new time/op    delta
    GetListIncremental-8    7.29ms ± 2%    6.53ms ± 1%  -10.50%  (p=0.000 n=9+9)

    name                   old alloc/op   new alloc/op   delta
    GetListIncremental-8    1.30kB ±13%    0.70kB ± 5%  -46.38%  (p=0.000 n=9+10)

    name                  old allocs/op  new allocs/op  delta
    GetListIncremental-8      33.2 ±11%      18.0 ± 0%  -45.82%  (p=0.000 n=9+10)

Updates #5958

Change-Id: I4be83463cbd23c2e2fa5d0bdf38560004f53401b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 3697609aaa portlist: remove unix.Readlink allocs on Linux
name       old time/op    new time/op    delta
    GetList-8    11.2ms ± 5%    11.1ms ± 3%     ~     (p=0.661 n=10+9)

    name       old alloc/op   new alloc/op   delta
    GetList-8    83.3kB ± 1%    67.4kB ± 1%  -19.05%  (p=0.000 n=10+10)

    name       old allocs/op  new allocs/op  delta
    GetList-8     2.89k ± 2%     2.19k ± 1%  -24.24%  (p=0.000 n=10+10)

(real issue is we're calling this code as much as we are, but easy
enough to make it efficient because it'll still need to be called
sometimes in any case)

Updates #5958

Change-Id: I90c20278d73e80315a840aed1397d24faa308d93
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 7149155b80 portlist: further reduce allocations on Linux
Make Linux parsePorts also an append-style API and attach it to
caller's provided append base memory.

And add a little string intern pool in front of the []byte to string
for inode names.

    name       old time/op    new time/op    delta
    GetList-8    11.1ms ± 4%     9.8ms ± 6%  -11.68%  (p=0.000 n=9+10)

    name       old alloc/op   new alloc/op   delta
    GetList-8    92.8kB ± 2%    79.7kB ± 0%  -14.11%  (p=0.000 n=10+9)

    name       old allocs/op  new allocs/op  delta
    GetList-8     2.94k ± 1%     2.76k ± 0%   -6.16%  (p=0.000 n=10+10)

More coming. (the bulk of the allocations are in addProcesses and
filesystem operations, most of which we should usually be able to
skip)

Updates #5958

Change-Id: I3f0c03646d314a16fef7f8346aefa7d5c96701e7
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 46ce80758d portlist: update some internals to use append-style APIs
In prep for reducing garbage, being able to reuse memory.  So far this
doesn't actually reuse much. This is just changing signatures around.

But some improvement in any case:

    bradfitz@tsdev:~/src/tailscale.com$ ~/go/bin/benchstat before after
    name       old time/op    new time/op    delta
    GetList-8    11.8ms ± 9%     9.9ms ± 3%  -15.98%  (p=0.000 n=10+10)

    name       old alloc/op   new alloc/op   delta
    GetList-8    99.5kB ± 2%    91.9kB ± 0%   -7.62%  (p=0.000 n=9+9)

    name       old allocs/op  new allocs/op  delta
    GetList-8     3.05k ± 1%     2.93k ± 0%   -3.83%  (p=0.000 n=8+9)

More later, once parsers can reuse strings from previous parses.

Updates #5958

Change-Id: I76cd5048246dd24d11c4e263d8bb8041747fb2b0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Eng Zer Jun f0347e841f refactor: move from io/ioutil to io and os packages
The io/ioutil package has been deprecated as of Go 1.16 [1]. This commit
replaces the existing io/ioutil functions with their new definitions in
io and os packages.

Reference: https://golang.org/doc/go1.16#ioutil
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
2 years ago
Brad Fitzpatrick 4950fe60bd syncs, all: move to using Go's new atomic types instead of ours
Fixes #5185

Change-Id: I850dd532559af78c3895e2924f8237ccc328449d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 0eb6cc9321 portlist: cache field index position between runs, cut two more allocs (Linux)
name          old time/op    new time/op    delta
ParsePorts-6    6.41ms ± 7%    3.15ms ± 2%  -50.84%  (p=0.000 n=9+9)

name          old alloc/op   new alloc/op   delta
ParsePorts-6      408B ± 0%      216B ± 0%  -47.06%  (p=0.002 n=8+10)

name          old allocs/op  new allocs/op  delta
ParsePorts-6      7.00 ± 0%      4.00 ± 0%  -42.86%  (p=0.000 n=10+10)

Updates tailscale/corp#2566

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 61f201f33d portlist: reuse bufio.Reader between files
name         old time/op    new time/op    delta
ListPorts-6    1.18ms ± 5%    1.16ms ± 5%     ~     (p=0.075 n=10+10)

name         old alloc/op   new alloc/op   delta
ListPorts-6    27.2kB ± 0%    14.9kB ± 0%  -45.14%  (p=0.001 n=8+9)

name         old allocs/op  new allocs/op  delta
ListPorts-6      90.0 ± 0%      84.0 ± 0%   -6.67%  (p=0.000 n=10+10)

Updates tailscale/corp#2566

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 5a9d977c78 portlist: reduce CPU parsing portlist
Avoid splitting fields in the common case. Field splitting was 84% of
the overall CPU.

name          old time/op    new time/op    delta
ParsePorts-6    33.3ms ± 2%     6.3ms ± 4%  -80.97%  (p=0.000 n=9+10)

name          old alloc/op   new alloc/op   delta
ParsePorts-6      520B ±79%      408B ± 0%  -21.49%  (p=0.046 n=10+8)

name          old allocs/op  new allocs/op  delta
ParsePorts-6      7.00 ± 0%      7.00 ± 0%     ~     (all equal)

Updates tailscale/corp#2566

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 64e9ce8df1 portlist: reduce allocs on Linux
Notably, it no longer allocates proportional to the number of open
sockets on the machine. Any alloc reduction numbers are a little
contrived with such a reduction but e.g. on a machine with 50,000
connections open:

name          old time/op    new time/op    delta
ParsePorts-6    57.7ms ± 6%    32.8ms ± 3%   -43.04%  (p=0.000 n=9+10)

name          old alloc/op   new alloc/op   delta
ParsePorts-6    24.0MB ± 0%     0.0MB ± 0%  -100.00%  (p=0.000 n=10+9)

name          old allocs/op  new allocs/op  delta
ParsePorts-6      100k ± 0%        0k ± 0%   -99.99%  (p=0.000 n=10+10)

Updates tailscale/corp#2566

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 2df6372b67 portlist: de-dup services on same (proto, port) on both IPv4/IPv6
Fixes #1703

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
Brad Fitzpatrick b0af15ff5c portlist: remove some old TODOs
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
4 years ago
David Anderson 63a9adeb6c portlist: collect IPv6 listening sockets on linux.
This is important because some of those v6 sockets are actually
dual-stacked sockets, so this is our only chance of discovering
some services.

Fixes #1443.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
David Anderson ad6edf5ecd portlist: report a better process name for .Net on linux.
Fixes #1440.

Signed-off-by: David Anderson <danderson@tailscale.com>
4 years ago
Brad Fitzpatrick 77cad13c70 portlist: avoid syscall audit violation logspam on Android
If we don't have access, don't try, don't log, don't continue trying.

Fixes #521
4 years ago
Avery Pennarun 806de4ac94 portlist: fix "readdirent: no such file or directory" errors on Linux.
This could happen when a process disappeared while we were reading its
file descriptor list.

I was able to replicate the problem by running this in another
terminal:

    while :; do for i in $(seq 10); do
      /bin/true & done >&/dev/null; wait >&/dev/null;
    done

And then running the portlist tests thousands of times.

Fixes #339.

Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
5 years ago
Wendi Yu fde384b359 Fix macOS build
staticcheck used to fail on macOS (and presumably windows) due to a
variable declared in a common package that was only used by the Linux
build, which would prevent `redo pr` from passing on Mac. Moved variable
declaration from the common file to the Linux-specific one to resolve
the compiler complaint.

Signed-off-by: Wendi Yu <wendi.yu@yahoo.ca>
5 years ago
Brad Fitzpatrick 3b546dc29a portlist: make two error paths have unique messages
For debugging #339
5 years ago
Brad Fitzpatrick f8d67bb591 portlist: ignore ports bound to localhost
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
5 years ago
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>
5 years ago
Earl Lee a8d8b8719a Move Linux client & common packages into a public repo. 5 years ago