Commit Graph

8 Commits

Author SHA1 Message Date
Wilmer Paulino
977c139f3c
discovery: handle graph synced status after stalled initial historical sync
This ensures that the graph synced status is marked true at some point
once a historical sync has completed. Before this commit, a stalled
historical sync could cause us to never mark the graph as synced.
2019-08-06 17:56:55 -07:00
Wilmer Paulino
af4234f680
discovery: allow the SyncManager to report whether the graph is synced 2019-08-06 17:56:54 -07:00
Johan T. Halseth
6ba6982ae7
discovery/sync_manager_test: add TestSyncManagerHistoricalSyncOnReconnect
TestSyncManagerHistoricalSyncOnReconnect tests that the sync manager will
re-trigger a historical sync when a new peer connects after a historical
sync has completed, but we have lost all peers.
2019-05-24 11:05:30 +02:00
Wilmer Paulino
d68842ee9e
discovery: queue active syncers until initial historical sync signal
In this commit, we begin to queue any active syncers until the initial
historical sync has completed. We do this to ensure we can properly
handle any new channel updates at tip. This is required for fresh nodes
that are syncing the channel graph for the first time. If we begin
accepting updates at tip while the initial historical sync is still
ongoing, then we risk not processing certain updates since we've yet to
learn of the channels themselves.
2019-04-24 13:20:57 -07:00
Wilmer Paulino
07136a5bc2
discovery: handle initial historical sync disconnection
In this commit, we add logic to handle a peer with whom we're performing
an initial historical sync disconnecting. This is required to ensure we
get as much of the graph as possible when starting a fresh node. It will
also serve useful to ensure we do not get stalled once we prevent active
GossipSyncers from starting until the initial historical sync has
completed.
2019-04-24 13:20:55 -07:00
Wilmer Paulino
29baa12254
discovery: synchronize new/stale GossipSyncers with syncerHandler
Now that the roundRobinHandler is no longer present, this commit aims to
clean up and simplify some of the logic surrounding initializing/tearing
down new/stale GossipSyncers from the SyncManager. Along the way, we
also synchronize these calls with the syncerHandler, which will serve
useful in future work that allows us to recovery from initial historical
sync disconnections.
2019-04-24 13:19:09 -07:00
Wilmer Paulino
5db2cf6273
discovery+server: remove roundRobinHandler and related code
Since ActiveSync GossipSyncers no longer synchronize our state with the
remote peers, none of the logic surrounding the round-robin is required
within the SyncManager.
2019-04-24 13:19:07 -07:00
Wilmer Paulino
a188657b2f
discovery: introduce gossiper SyncManager subsystem
In this commit, we introduce a new subsystem for the gossiper: the
SyncManager. This subsystem is a major overhaul on the way the daemon
performs the graph query sync state machine with peers.

Along with this subsystem, we also introduce the concept of an active
syncer. An active syncer is simply a GossipSyncer currently operating
under an ActiveSync sync type. Before this commit, all GossipSyncer's
would act as active syncers, which means that we were receiving new
graph updates from all of them. This isn't necessary, as it greatly
increases bandwidth usage as the network grows. The SyncManager changes
this by requiring a specific number of active syncers. Once we reach
this specified number, any future peers will have a GossipSyncer with a
PassiveSync sync type.

It is responsible for three main things:

1. Choosing different peers randomly to receive graph updates from to
ensure we don't only receive them from the same set of peers.

2. Choosing different peers to force a historical sync with to ensure we
have as much of the public network as possible. The first syncer
registered with the manager will also attempt a historical sync.

3. Managing an in-order queue of active syncers where the next cannot be
started until the current one has completed its state machine to ensure
they don't overlap and request the same set of channels, which
significantly reduces bandwidth usage and addresses a number of issues.
2019-04-03 15:08:32 -07:00