wgengine/magicsock,types/logger: add latency logs for initial peer contacts (#19916)

In order to allow us to measure the performance effects of client-side netmap
caching, both with and without the feature enabled, add logs to record how long
it takes after a client restart or profile switch for the node to establish
contact with peers, relative to the first uncached netmap.

We do this by keeping track of a timestamp when the connection is constructed,
and logging a record for "new" peer contacts that records how long (in
microseconds) it took from the time the peer was recorded as a candidate.  The
message includes whether the contact was via DERP or direct, and whether a
cached netmap was in use at the time.

This builds on and extends the counters from #19699, but here we include new
contacts whether or not a cached netmap is in use, so that we can establish a
baseline for comparison.

Updates #12639
Updates tailscale/projects#27

Change-Id: I4f6d050e221f3881848d05a0425c4a5d1a59294c
Signed-off-by: M. J. Fromberger <fromberger@tailscale.com>

This commit is contained in:

M. J. Fromberger

2026-06-02 07:34:17 -07:00

committed by

GitHub

parent c898aeb0d8

commit a3bec699dc

3 changed files with 46 additions and 15 deletions

									
										types/logger/logger.go
									
		+1
		
												View File
												
				@@ -141,6 +141,7 @@ var rateFree = []string{

					"magicsock: disco: ",

					"magicsock: ParseEndpoint:",

					// grinder stats lines

					"magicsock: new contact: ",

					"SetPrefs: %v",

					"peer keys: %s",

					"v%v peers: %v",