This test set the bar too high.
Just a couple of missed timers was enough to fail.
Change the test to more of a sanity check.
While we're here, run it for just 1s instead of 5s.
Prior to this change, on a 13" M1 MPB, with
stress -p 512 ./rate.test -test.run=QPS
I saw 90%+ failures.
After this change, I'm at 30k runs with no failures yet.
Fixes#3733
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
This test is highly dependent on the accuracy of OS timers.
Reduce the number of failures by decreasing the required
accuracy from 0.999 to 0.995.
Also, switch from repeated time.Sleep to using a time.Ticker
for improved accuracy.
Updates #2727
Signed-off-by: Joe Tsai <joetsai@digital-static.net>
This is a simplified rate limiter geared for exactly our needs:
A fast, mono.Time-based rate limiter for use in tstun.
It was generated by stripping down the x/time/rate rate limiter
to just our needs and switching it to use mono.Time.
It removes one time.Now call per packet.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
