New-style IPN bus subscribers consume stateful delta streams. Reject
NotifyRateLimit when it is combined with those subscription bits so
tailscaled cannot merge or delay messages that clients need to apply in
order.
Also stop silently dropping notifications when a watcher falls behind.
Remove the watcher, replace its stale queue with one terminal ErrMessage
notification, and close the watch.
Updates #20062
Change-Id: Id9d402ea76f4011cd23f122adf62f30dd4b6f90b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
For large tailnets (~50k+ nodes) with frequent peer churn (ephemeral
GitHub Actions workers etc.), tailscaled used to rebuild the full
netmap and fan it out on the IPN bus on every MapResponse that
added or removed a peer. There were two O(N) costs per delta: the
full netmap rebuild + every Notify.NetMap encode to every bus watcher.
This change tackles both:
1. Plumb O(1) peer add/remove through the delta path. PeersChanged
and PeersRemoved no longer prevent the delta happy path; instead,
they mutate the per-node-backend peer map in place.
2. Restrict ipn.Notify.NetMap emission to the platforms whose host
GUIs still depend on it (Windows, macOS, iOS) and migrate
in-tree consumers off it everywhere else:
- Migrate reactive consumers (containerboot, kube agents,
sniproxy, tsconsensus, etc.) off Notify.NetMap to the
previously-added Notify.SelfChange signal so they no longer
have to subscribe to the full netmap.
- Add ipn.NotifyNoNetMap so GUI clients on "legacy-emit" platforms
that have already migrated can opt out of the per-watcher
NetMap encode.
- Gate Notify.NetMap emission on the producer side by a compile-
time GOOS check, so the supporting code is dead-code-eliminated
on Linux and other geese where no GUI consumer needs it.
Re-running BenchmarkGiantTailnet from tstest/largetailnet, which was
added along with baseline numbers on unmodified main in ad5436af0d,
the per-delta cost (one peer add+remove pair) is now ~O(1) regardless
of tailnet size N:
N no-watcher (ms/op) bus-watcher (ms/op)
before now factor before now factor
10000 32 0.11 300x 166 0.13 1300x
50000 222 0.11 2000x 865 0.13 6700x
100000 504 0.12 4100x 1765 0.13 13400x
250000 1551 0.12 12500x 4696 0.15 32400x
Updates #12542
Change-Id: I94e34b37331d1a8ec74c299deffadf4d061fda9e
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Add a new bus signal that lets reactive consumers (containerboot, kube
agents, sniproxy, tsconsensus, etc.) react to self-node updates without
having to subscribe to the full netmap. Today those consumers either
watch Notify.NetMap (which on large tailnets is expensive to encode and
ship per watcher) or poll. SelfChange is a cheap, narrow alternative:
addresses, name, key expiry, capabilities, etc.
Consumers that need additional state can react to SelfChange and then
fetch the relevant bits on demand via existing LocalClient methods.
Producer-side, every netmap-bearing setControlClientStatus call now
also publishes SelfChange. Future changes will migrate individual
in-tree consumers off Notify.NetMap to this signal, and eventually
gate the legacy NetMap emission to platforms whose host GUIs still
require it.
Updates #12542
Change-Id: I4441650b0e085d663eb6bf26a03748b7d961ca49
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
ipn/local: add netmap mutations to the ipn bus
updates tailscale/tailscale#1909
This adds a new new NotifyWatchOpt that allows watchers to
receive PeerChange events (derived from node mutations)
on the IPN bus in lieu of a complete netmap. We'll continue
to send the full netmap for any map response that includes it,
but for mutations, sending PeerChange events gives the client
the option to manage it's own models more selectively and cuts
way down on json serialization overhead.
On chatty tailnets, this will vastly reduce the amount of
chatter on the bus.
This change should be backwards compatible, it is
purely additive. Clients that subscribe to NotifyNetmap will
get the full netmap for every delta. New clients can
omit that and instead opt into NotifyPeerChanges.
Signed-off-by: Jonathan Nobels <jonathan@tailscale.com>
This file was never truly necessary and has never actually been used in
the history of Tailscale's open source releases.
A Brief History of AUTHORS files
---
The AUTHORS file was a pattern developed at Google, originally for
Chromium, then adopted by Go and a bunch of other projects. The problem
was that Chromium originally had a copyright line only recognizing
Google as the copyright holder. Because Google (and most open source
projects) do not require copyright assignemnt for contributions, each
contributor maintains their copyright. Some large corporate contributors
then tried to add their own name to the copyright line in the LICENSE
file or in file headers. This quickly becomes unwieldy, and puts a
tremendous burden on anyone building on top of Chromium, since the
license requires that they keep all copyright lines intact.
The compromise was to create an AUTHORS file that would list all of the
copyright holders. The LICENSE file and source file headers would then
include that list by reference, listing the copyright holder as "The
Chromium Authors".
This also become cumbersome to simply keep the file up to date with a
high rate of new contributors. Plus it's not always obvious who the
copyright holder is. Sometimes it is the individual making the
contribution, but many times it may be their employer. There is no way
for the proejct maintainer to know.
Eventually, Google changed their policy to no longer recommend trying to
keep the AUTHORS file up to date proactively, and instead to only add to
it when requested: https://opensource.google/docs/releasing/authors.
They are also clear that:
> Adding contributors to the AUTHORS file is entirely within the
> project's discretion and has no implications for copyright ownership.
It was primarily added to appease a small number of large contributors
that insisted that they be recognized as copyright holders (which was
entirely their right to do). But it's not truly necessary, and not even
the most accurate way of identifying contributors and/or copyright
holders.
In practice, we've never added anyone to our AUTHORS file. It only lists
Tailscale, so it's not really serving any purpose. It also causes
confusion because Tailscalars put the "Tailscale Inc & AUTHORS" header
in other open source repos which don't actually have an AUTHORS file, so
it's ambiguous what that means.
Instead, we just acknowledge that the contributors to Tailscale (whoever
they are) are copyright holders for their individual contributions. We
also have the benefit of using the DCO (developercertificate.org) which
provides some additional certification of their right to make the
contribution.
The source file changes were purely mechanical with:
git ls-files | xargs sed -i -e 's/\(Tailscale Inc &\) AUTHORS/\1 contributors/g'
Updates #cleanup
Change-Id: Ia101a4a3005adb9118051b3416f5a64a4a45987d
Signed-off-by: Will Norris <will@tailscale.com>
fixestailscale/corp#26369
The suggested exit node is currently only calculated during a localAPI request.
For older UIs, this wasn't a bad choice - we could just fetch it on-demand when a menu
presented itself. For newer incarnations however, this is an always-visible field
that needs to react to changes in the suggested exit node's value.
This change recalculates the suggested exit node ID on netmap updates and
broadcasts it on the IPN bus. The localAPI version of this remains intact for the
time being.
Signed-off-by: Jonathan Nobels <jonathan@tailscale.com>
I merged 5cae7c51bf (removing Notify.BackendLogID) and 93db503565
(adding another reference to Notify.BackendLogID) that didn't have merge
conflicts, but didn't compile together.
This removes the new reference, fixing the build.
Updates #14129
Change-Id: I9bb68efd977342ea8822e525d656817235039a66
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Limit spamming GUIs with boring updates to once in 3 seconds, unless
the notification is relatively interesting and the GUI should update
immediately.
This is basically @barnstar's #14119 but with the logic moved to be
per-watch-session (since the bit is per session), rather than
globally. And this distinguishes notable Notify messages (such as
state changes) and makes them send immediately.
Updates tailscale/corp#24553
Change-Id: I79cac52cce85280ce351e65e76ea11e107b00b49
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Brad FitzpatrickandBrad Fitzpatrick
Jonathan NobelsandGitHub
Will NorrisandWill Norris