This commit changes the gossiper to direct messages to
peer objects, instead of sending them through the
server every time. The primary motivation is to reduce
contention on the server's mutex and, more importantly,
avoid deadlocks in the Triangle of Death.
In this commit, we fix an existing deadlock in the
gossiper->server->peer pipeline by ensuring that we're not holding the
syncer mutex while we attempt to have a syncer filter out the rest of
gossip messages.
In this commit we fix an existing bug caused by a scheduling race
condition. We'll now ensure that if we get a gossip message from a peer
before we create an instance for it, then we create one on the spot so
we can service the message. Before this commit, we would drop the first
message, and therefore never sync up with the peer at all, causing them
to miss channel announcements.
In this commit, we extend the AuthenticatedGossiper to take advantage of
the new query features in the case that it gets a channel update w/o
first receiving the full channel announcement. If this happens, we'll
attempt to find a syncer that's fully synced, and request the channel
announcement from it.
In this commit, we create a new concrete implementation for the new
discovery.ChannelGraphTimeSeries interface. We also export the
createChannelAnnouncement method to allow the chanSeries struct to
re-use the existing code for creating wire messages from the database
structs.
In this commit, we update the logic in the AuthenticatedGossiper to
ensure that can properly create, manage, and dispatch messages to any
gossipSyncer instances created by the server.
With this set of changes, the gossip now has complete knowledge of the
current set of peers we're conneted to that support the new range
queries. Upon initial connect, InitSyncState will be called by the
server if the new peer understands the set of gossip queries. This will
then create a new spot in the peerSyncers map for the new syncer. For
each new gossip query message, we'll then attempt to dispatch the
message directly to the gossip syncer. When the peer has disconnected,
we then expect the server to call the PruneSyncState method which will
allow us to free up the resources.
Finally, when we go to broadcast messages, we'll send the messages
directly to the peers that have gossipSyncer instances active, so they
can properly be filtered out. For those that don't we'll broadcast
directly, ensuring we skip *all* peers that have an active gossip
syncer.
In this commit, introduce a new struct, the gossipSyncer. The role of
this struct is to encapsulate the state machine required to implement
the new gossip query range feature recently added to the spec. With this
change, each peer that knows of this new feature will have a new
goroutine that will be managed by the gossiper.
Once created and started, the gossipSyncer will start to progress
through each possible state, finally ending at the chansSynced stage. In
this stage, it has synchronized state with the remote peer, and is
simply awaiting any new messages from the gossiper to send directly to
the peer. Each message will only be sent if the remote peer actually has
a set update horizon, and the message isn't before or after that
horizon.
A set of unit tests has been added to ensure that two state machines
properly terminate and synchronize channel state.
In this commit, we update the testUpdateChannelPolicy to exercise the
recent set of changes within the switch. If one applies this test to a
fresh branch (without those new changes) it should fail. This is due to
the fact that before, Bob would attempt to apply the constraints of the
incoming link (which we updated) instead of the outgoing link. With the
recent set of changes, the test now properly passes.
In this commit, we fix an existing deadlock in the
processChanPolicyUpdate method. Before this commit, within
processChanPolicyUpdate, we would directly call updateChannel *within*
the ForEachChannel closure. This would at times result in a deadlock, as
updateChannel will itself attempt to create a write transaction in order
to persist the newly updated channel.
We fix this deadlock by simply performing another loop once we know the
set of channels that we wish to update. This second loop will actually
update the channels on disk.
In this commit, we reduce the amount of unnecessary work that the
gossiper can carry out. When CPU profiling some nodes, I noticed that
we’d spend a lot of time validating the signatures for an announcement,
only to realize that the router already had it.
To remedy this, we’ll use the new methods added to the channel router
in order to avoid unnecessarily validating an announcement that is
actually stale. This should reduce memory usage (since it uses big
int’s under the scenes), and also idle CPU usage.
In order to reduce high CPU utilization during the initial network view
sync, we slash down the total number of active in-flight jobs that can
be launched.
This commit uses the multimutex.Mutex to esure database
state stays consistent when handling an announcement, by
restricting access to one goroutine per channel ID.
This fixes a bug where the goroutine would read the
database, make some decisions based on what was read,
then write its data to the database, but the read data
would be outdated at this point. For instance, an
AuthProof could have been added between reading the
database and when the decision whether to announce
the channel is made, making it not announce it.
Similarly, when receiving the AuthProof, the edge
policy could be added between reading the edge state
and adding the proof to the database, also resulting
in the edge not being announced.
This commit fixes a bug that could cause annoucements
to get lost, and resultet in flaky integration tests.
After a set of announcements was broadcastet, we would
reset (clear) the announcement batch, making any
annoucement that was added between the call to Emit()
and Reset() to be deleted, without ever being broadcast.
We can just remove the Reset() call, as the batch will
actually be reset within the call to Emit(), making
the previous call only delete those messages we hadn't
sent yet.
We no longer need to hand off new channels that come online as the
chainWatcher will be persistent, and always have an active signal for
the entire lifetime of the channel.
This commit ensures that we always increment the timestamp of
ChannelUpdates we send telling the network about changes to
our channel policy. We do this because it could happen
(especially during tests) that we issued an update, but the
ChannelUpdate would have the same timestamp as our last
ChannelUpdate, and would be ignored by the network.
This commit makes the gossiper aware of the timestamps
of ChannelUpdates and NodeAnnouncements, such that it
only keeps the newest message when deduping. Earlier
it would always keep the last received message, which
in some cases could be outdated.
This commit makes sure we are not attempting to create a
channel announcement with a nil ChannelAuthProof, as that
could cause a crash at startup whe the gossiper would
attempt to reprocess an edge coming from the fundingmanager.
It also makes sure we check the correct error returned from
processRejectedEdge.
In this commit, we make an incremental step towards page of the new
feature of deDupedAnnoucnements to return the set of senders for each
message. All methods the process new channel announcements, will now
return an instance of networkMsg rather than lnwire.Message. This will
allow passing the returned announcement directly into
deDupedAnnoucnements.AddMsg().
In this commit, we modify the deDupedAnnouncements struct slightly. The
element of this struct will now keep track of the set of senders that
sent a particular message. Each time a message is added, we’ll replace
the new message with the old (as normal), but we’ll also add the new
sender to the set of known senders.
With this new feature, we’ll be able to avoid re-sending a message to
the peer that sent it to us in the first place.
This commit makes the gossiper track the state of a local
AnnounceSignature message, such that it can retry sending
it to the remote peer if needed. It will also persist this
state in the WaitingProofStore, such that it can resume
from this state at startup.
This commit makes the gossiper store received ChannelUpdates
that is not for any known channel in a map, such that they
can be reprocessed when the ChannelAnnouncement arrives.
This is done to handle the case where we receive a ChannelUpdate
from our channel counterparty before we have been able to process
our own local ChannelAnnouncement.
This commit adds some comments and does some cleanup
of the logic that makes sure non-public channels
(channels with no AuthProof) are not broadcasted
to the network.
This commit fixes an existing bug wherein we would blank out a node’s
color instead of properly setting the field when syncing graph state
with another node This would cause the node to reject the node
announcement and we would generate an we would invalidate the signature
of the node announcement. We fix this simply by properly setting the
node announcement.
In this commit, we fix an existing bug when processing new node
announcement. Before this commit, we wouldn’t also copy over the color
field of a node’s announcement. As a result, when went to synchronize
our graph state with that of a connecting peer, we would generate an
invalid node announcement. We fix this by properly setting the color
field of a node.
In this commit, we now properly examine the Flag field within the
ChannelUpdate message as a bitfield. Before this commit we would
manually check the flags for zero or one. This was incorrect as a their
bit has now been defined. To properly dispatch the messages, we’ll now
treat it properly as a bitmask.
