Commit Graph

13 Commits (fd92fbd69efb40747aee7902bc7ca96222d7e5d3)

Author SHA1 Message Date
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 70dde89c34 portlist: add package doc, file comments, move a method to the right file
And respect envknob earlier. NewPoller has one caller and ignores
errors; they just signal ipnlocal to log a warning and not use the
portlist poller.

Change-Id: I4a33af936fe780cca8c7197d4d74ac31a1dc01e3
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
Brad Fitzpatrick 67597bfc9e portlist: unexport GetList
It's an internal implementation detail, and I plan to refactor it
for performance (garbage) reasons anyway, so start by hiding it.

Updates #5958

Change-Id: I2c0d1f743d3495c5f798d1d8afc364692cd9d290
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 74674b110d envknob: support changing envknobs post-init
Updates #5114

Change-Id: Ia423fc7486e1b3f3180a26308278be0086fae49b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 41fd4eab5c envknob: add new package for all the strconv.ParseBool(os.Getenv(..))
A new package can also later record/report which knobs are checked and
set. It also makes the code cleaner & easier to grep for env knobs.

Change-Id: Id8a123ab7539f1fadbd27e0cbeac79c2e4f09751
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick a05086ef86 portlist: add debug knob to disable portlist collection
For big servers. Per discussion with @crawshaw.

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 5c5acadb2a portlist: unexport SameInodes method
Signed-off-by: Brad Fitzpatrick <brad@danga.com>
4 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 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