From 4a2871ff52b58772c5bb540388962b6fcb09fcb6 Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Fri, 29 Jun 2012 03:50:37 -0700
Subject: [PATCH] Timing routines for continuous ledger close.

---
 src/LedgerTiming.cpp | 58 ++++++++++++++++++++++++++++++++++++++++++++
 src/LedgerTiming.h   | 44 ++++++++++++++++++++++-----------
 2 files changed, 88 insertions(+), 14 deletions(-)
 create mode 100644 src/LedgerTiming.cpp

diff --git a/src/LedgerTiming.cpp b/src/LedgerTiming.cpp
new file mode 100644
index 0000000000..d50eb3d85a
--- /dev/null
+++ b/src/LedgerTiming.cpp
@@ -0,0 +1,58 @@
+
+#include "LedgerTiming.h"
+
+
+// Returns the number of seconds the ledger was or should be open
+int ContinuousLedgerTiming::shouldClose(	// How many:
+	bool anyTransactions,
+	int previousProposers,		// proposers there were in the last closing
+	int proposersClosed,		// proposers who have currently closed their ledgers
+	int previousOpenSeconds,	// seconds the previous ledger was open
+	int currentOpenSeconds)		// seconds since the previous ledger closed
+{
+	if (!anyTransactions)
+	{ // no transactions so far this interval
+		if (previousOpenSeconds > (LEDGER_IDLE_INTERVAL + 2)) // the last ledger was very slow to close
+			return previousOpenSeconds - 1;
+		return LEDGER_IDLE_INTERVAL; // normal idle
+	}
+
+	if (previousOpenSeconds == LEDGER_IDLE_INTERVAL) // coming out of idle, close now
+		return currentOpenSeconds;
+
+	// If the network is slow, try to synchronize close times
+	if (previousOpenSeconds > 8)
+		return (currentOpenSeconds - currentOpenSeconds % 4);
+	else if (previousOpenSeconds > 4)
+		return (currentOpenSeconds - currentOpenSeconds % 2);
+
+	return currentOpenSeconds; // this ledger should close now
+}
+
+bool ContinuousLedgerTiming::haveConsensus(
+	int previousProposers,		// proposers in the last closing (not including us)
+	int currentProposers,		// proposers in this closing so far (not including us)
+	int currentAgree,			// proposers who agree with us
+	int currentClosed,			// proposers who have currently closed their ledgers
+	int previousAgreeTime,		// how long it took to agree on the last ledger
+	int currentAgreeTime)		// how long we've been trying to agree
+{
+	if (currentProposers < (previousProposers * 3 / 4))
+	{ // Less than 3/4 of the validators are present, slow down
+		if (currentAgreeTime < (previousAgreeTime + 2))
+			return false;
+	}
+
+	// If 80% of current proposers (plus us) agree on a set, we have consensus
+	int agreeWeight = (currentAgree * 100 + 100) / (currentProposers + 1);
+	if (agreeWeight > 80)
+		return true;
+
+	// If 50% of the nodes on your UNL (minus us) have closed, you should close
+	int closeWeight = (currentClosed * 100 - 100) / (currentProposers + 1);
+	if (closeWeight > 50)
+		return true;
+
+	return false;
+}
+	
\ No newline at end of file
diff --git a/src/LedgerTiming.h b/src/LedgerTiming.h
index d7e623844d..5431443282 100644
--- a/src/LedgerTiming.h
+++ b/src/LedgerTiming.h
@@ -21,30 +21,46 @@
 // Maximum converge time
 #	define LEDGER_MAX_CONVERGE		20
 
+#define AV_PCT_STOP					85
 
 #endif
 
-#ifdef LEDGER_CLOSE_SLOW
-
-#	define LEDGER_INTERVAL			1800
-
-#	define LEDGER_FORCE_CONVERGE	180
-
-#	define LEDGER_CONVERGE			240
 
 
-// Time a transaction must be unconflicted before we consider it protected
-#	define LEDGER_PROTECT		90
+// BEGIN LEDGER_CLOSE_CONTINUOUS
 
-#endif
+// The number of seconds a ledger may remain idle before closing
+#	define LEDGER_IDLE_INTERVAL		15
+
+// How long we wait to transition from inactive to active
+#	define LEDGER_IDLE_SPIN_TIME	2
 
 // Avalance tuning (percent of UNL voting yes for us to vote yes)
-#define AV_MIN_CONSENSUS			50
-#define AV_AVG_CONSENSUS			60
+#define AV_MIN_CONSENSUS			55
+#define AV_AVG_CONSENSUS			65
 #define AV_MAX_CONSENSUS			70
 
-// We consider consensus reached at this percent agreement
-#define AV_PCT_STOP					90
+
+class ContinuousLedgerTiming
+{
+public:
+
+	// Returns the number of seconds the ledger was or should be open
+	// Call when a consensus is reached and when any transaction is relayed to be added
+	static int shouldClose(
+		bool anyTransactions,
+		int previousProposers,		int proposersClosed,
+		int previousOpenSeconds,	int currentOpenSeconds);
+
+	static bool haveConsensus(
+		int previousProposers,		int currentProposers,
+		int currentAgree,			int currentClosed,
+		int previousAgreeTime,		int currentAgreeTime);
+
+};
+
+// END LEDGER_CLOSE_CONTINUOUS
+
 
 
 #endif