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>
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>
And it updates the build tag style on a couple files.
Change-Id: I84478d822c8de3f84b56fa1176c99d2ea5083237
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
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>
