Commit Graph

2 Commits (20324eeebc97d339561c13955eecb0fb4872359e)

Author SHA1 Message Date
James Tucker 539c073cf0 wgengine/magicsock: set UDP socket buffer sizes to 7MB
- At high data rates more buffer space is required in order to avoid
  packet loss during any cause of delay.
- On slower machines more buffer space is required in order to avoid
  packet loss while decryption & tun writing is underway.
- On higher latency network paths more buffer space is required in order
  to overcome BDP.
- On Linux set with SO_*BUFFORCE to bypass net.core.{r,w}mem_max.
- 7MB is the current default maximum on macOS 12.6
- Windows test is omitted, as Windows does not support getsockopt for
  these options.

Signed-off-by: James Tucker <james@tailscale.com>
2 years ago
Andrew Dunham c72caa6672 wgengine/magicsock: use AF_PACKET socket + BPF to read disco messages
This is entirely optional (i.e. failing in this code is non-fatal) and
only enabled on Linux for now. Additionally, this new behaviour can be
disabled by setting the TS_DEBUG_DISABLE_AF_PACKET environment variable.

Updates #3824
Replaces #5474

Co-authored-by: Andrew Dunham <andrew@du.nham.ca>
Signed-off-by: David Anderson <danderson@tailscale.com>
2 years ago