tailscale/metrics
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>
2022-11-05 16:26:51 -07:00
..
fds_linux.go util/dirwalk, metrics, portlist: add new package for fast directory walking 2022-11-05 16:26:51 -07:00
fds_notlinux.go all: remove old +build tags 2022-11-04 07:25:42 -07:00
metrics.go metrics: move currentFDs code to the metrics package 2021-09-02 11:14:14 -07:00
metrics_test.go all: use testingutil.MinAllocsPerRun 2021-10-28 12:48:37 -07:00