From a181d2628772391cdc20461b3277ab943a896e35 Mon Sep 17 00:00:00 2001
From: Joost Jager <joost.jager@gmail.com>
Date: Thu, 8 Apr 2021 14:29:03 +0200
Subject: [PATCH] config: add channel commit interval parameter

---
 config.go        | 7 +++++++
 peer/brontide.go | 8 +++++++-
 sample-lnd.conf  | 5 +++++
 server.go        | 3 ++-
 4 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/config.go b/config.go
index be22891d..73f46c0d 100644
--- a/config.go
+++ b/config.go
@@ -141,6 +141,10 @@ const (
 	// commitment output.
 	// TODO(halseth): find a more scientific choice of value.
 	defaultMaxLocalCSVDelay = 10000
+
+	// defaultChannelCommitInterval is the default maximum time between receiving a
+	// channel state update and signing a new commitment.
+	defaultChannelCommitInterval = 50 * time.Millisecond
 )
 
 var (
@@ -289,6 +293,8 @@ type Config struct {
 	MaxChanSize                   int64         `long:"maxchansize" description:"The largest channel size (in satoshis) that we should accept. Incoming channels larger than this will be rejected"`
 	CoopCloseTargetConfs          uint32        `long:"coop-close-target-confs" description:"The target number of blocks that a cooperative channel close transaction should confirm in. This is used to estimate the fee to use as the lower bound during fee negotiation for the channel closure."`
 
+	ChannelCommitInterval time.Duration `long:"channel-commit-interval" description:"The maximum time that is allowed to pass between receiving a channel state update and signing the next commitment. Setting this to a longer duration allows for more efficient channel operations at the cost of latency."`
+
 	DefaultRemoteMaxHtlcs uint16 `long:"default-remote-max-htlcs" description:"The default max_htlc applied when opening or accepting channels. This value limits the number of concurrent HTLCs that the remote party can add to the commitment. The maximum possible value is 483."`
 
 	NumGraphSyncPeers      int           `long:"numgraphsyncpeers" description:"The number of peers that we should receive new graph updates from. This option can be tuned to save bandwidth for light clients or routing nodes."`
@@ -507,6 +513,7 @@ func DefaultConfig() Config {
 		DB:                      lncfg.DefaultDB(),
 		registeredChains:        chainreg.NewChainRegistry(),
 		ActiveNetParams:         chainreg.BitcoinTestNetParams,
+		ChannelCommitInterval:   defaultChannelCommitInterval,
 	}
 }
 
diff --git a/peer/brontide.go b/peer/brontide.go
index cb1f45fd..07c7f61c 100644
--- a/peer/brontide.go
+++ b/peer/brontide.go
@@ -308,6 +308,12 @@ type Config struct {
 	// ChannelLink.
 	ServerPubKey [33]byte
 
+	// ChannelCommitInterval is the maximum time that is allowed to pass between
+	// receiving a channel state update and signing the next commitment.
+	// Setting this to a longer duration allows for more efficient channel
+	// operations at the cost of latency.
+	ChannelCommitInterval time.Duration
+
 	// Quit is the server's quit channel. If this is closed, we halt operation.
 	Quit chan struct{}
 }
@@ -813,7 +819,7 @@ func (p *Brontide) addLink(chanPoint *wire.OutPoint,
 		UpdateContractSignals:   updateContractSignals,
 		OnChannelFailure:        onChannelFailure,
 		SyncStates:              syncStates,
-		BatchTicker:             ticker.New(50 * time.Millisecond),
+		BatchTicker:             ticker.New(p.cfg.ChannelCommitInterval),
 		FwdPkgGCTicker:          ticker.New(time.Hour),
 		PendingCommitTicker:     ticker.New(time.Minute),
 		BatchSize:               10,
diff --git a/sample-lnd.conf b/sample-lnd.conf
index 50ee6433..130c4067 100644
--- a/sample-lnd.conf
+++ b/sample-lnd.conf
@@ -264,6 +264,11 @@
 ; for the channel closure is not set.
 ; coop-close-target-confs=10
 
+; The maximum time that is allowed to pass between receiving a channel state
+; update and signing the next commitment. Setting this to a longer duration
+; allows for more efficient channel operations at the cost of latency.
+; channel-commit-interval=50ms
+
 ; The default max_htlc applied when opening or accepting channels. This value
 ; limits the number of concurrent HTLCs that the remote party can add to the
 ; commitment. The maximum possible value is 483.
diff --git a/server.go b/server.go
index e54348f9..11994894 100644
--- a/server.go
+++ b/server.go
@@ -3137,7 +3137,8 @@ func (s *server) peerConnected(conn net.Conn, connReq *connmgr.ConnReq,
 		CoopCloseTargetConfs:    s.cfg.CoopCloseTargetConfs,
 		MaxAnchorsCommitFeeRate: chainfee.SatPerKVByte(
 			s.cfg.MaxCommitFeeRateAnchors * 1000).FeePerKWeight(),
-		Quit: s.quit,
+		ChannelCommitInterval: s.cfg.ChannelCommitInterval,
+		Quit:                  s.quit,
 	}
 
 	copy(pCfg.PubKeyBytes[:], peerAddr.IdentityKey.SerializeCompressed())