Add Value, which measures the rate at which an event occurs,
exponentially weighted towards recent activity.
It is guaranteed to occupy O(1) memory, operate in O(1) runtime,
and is safe for concurrent use.
Signed-off-by: Joe Tsai <joetsai@digital-static.net>
This updates all source files to use a new standard header for copyright
and license declaration. Notably, copyright no longer includes a date,
and we now use the standard SPDX-License-Identifier header.
This commit was done almost entirely mechanically with perl, and then
some minimal manual fixes.
Updates #6865
Signed-off-by: Will Norris <will@tailscale.com>
The //go:build syntax was introduced in Go 1.17:
https://go.dev/doc/go1.17#build-lines
gofmt has kept the +build and go:build lines in sync since
then, but enough time has passed. Time to remove them.
Done with:
perl -i -npe 's,^// \+build.*\n,,' $(git grep -l -F '+build')
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
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>
Joe Tsai
Will Norris
Brad Fitzpatrick
Josh Bleecher Snyder