Commit Graph

4 Commits (6edf357b96b28ee1be659a70232c0135b2ffedfd)

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 d1cb7a2639 metrics: use SYS_OPENAT
New systems like arm64 don't even have SYS_OPEN.
3 years ago
Brad Fitzpatrick 99a1c74a6a metrics: optimize CurrentFDs to not allocate on Linux
It was 50% of our allocs on one of our servers. (!!)

Updates #2784

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick fc160f80ee metrics: move currentFDs code to the metrics package
Updates #2784

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago