From a3024352bae73bbcdbf95db652dfd0425ad8b14c Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Tue, 12 Nov 2013 13:18:55 -0800
Subject: [PATCH] Pathfinding improvements.

---
 src/ripple_app/ledger/LedgerMaster.cpp | 24 +++++++++++++++++++++++-
 src/ripple_app/ledger/LedgerMaster.h   |  1 +
 src/ripple_app/ledger/OrderBookDB.cpp  |  1 +
 src/ripple_app/paths/PathRequest.cpp   | 12 +++++++++++-
 src/ripple_app/paths/PathRequest.h     |  3 ++-
 5 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/src/ripple_app/ledger/LedgerMaster.cpp b/src/ripple_app/ledger/LedgerMaster.cpp
index 15ce7c2a0..146f907bd 100644
--- a/src/ripple_app/ledger/LedgerMaster.cpp
+++ b/src/ripple_app/ledger/LedgerMaster.cpp
@@ -924,9 +924,17 @@ void LedgerMaster::updatePaths (Job& job)
 {
     Ledger::pointer lastLedger;
 
+    if (getApp().getOPs().isNeedNetworkLedger ())
+    {
+        ScopedLockType ml (mLock, __FILE__, __LINE__);
+        mPathFindThread = false;
+        return;
+    }
+
     while (! job.shouldCancel())
     {
         bool newOnly = true;
+        bool hasNew = mPathFindNewRequest;
 
         {
             ScopedLockType ml (mLock, __FILE__, __LINE__);
@@ -952,7 +960,7 @@ void LedgerMaster::updatePaths (Job& job)
         }
 
         // VFALCO TODO Fix this global variable
-        PathRequest::updateAll (lastLedger, newOnly, job.getCancelCallback ());
+        PathRequest::updateAll (lastLedger, newOnly, hasNew, job.getCancelCallback ());
     }
 }
 
@@ -968,3 +976,17 @@ void LedgerMaster::newPathRequest ()
             BIND_TYPE (&LedgerMaster::updatePaths, this, P_1));
     }
 }
+
+// If the order book is radically updated, we need to reprocess all pathfinding requests
+void LedgerMaster::newOrderBookDB ()
+{
+    ScopedLockType ml (mLock, __FILE__, __LINE__);
+    mPathLedger.reset();
+
+    if (!mPathFindThread)
+    {
+        mPathFindThread = true;
+        getApp().getJobQueue ().addJob (jtUPDATE_PF, "updatePaths",
+            BIND_TYPE (&LedgerMaster::updatePaths, this, P_1));
+    }
+}
diff --git a/src/ripple_app/ledger/LedgerMaster.h b/src/ripple_app/ledger/LedgerMaster.h
index f95d89b35..89104e484 100644
--- a/src/ripple_app/ledger/LedgerMaster.h
+++ b/src/ripple_app/ledger/LedgerMaster.h
@@ -213,6 +213,7 @@ public:
 
     void tryAdvance ();
     void newPathRequest ();
+    void newOrderBookDB ();
 
     static bool shouldAcquire (uint32 currentLedgerID, uint32 ledgerHistory, uint32 targetLedger);
 
diff --git a/src/ripple_app/ledger/OrderBookDB.cpp b/src/ripple_app/ledger/OrderBookDB.cpp
index 6e3ea26b0..11705efd7 100644
--- a/src/ripple_app/ledger/OrderBookDB.cpp
+++ b/src/ripple_app/ledger/OrderBookDB.cpp
@@ -116,6 +116,7 @@ void OrderBookDB::update (Ledger::pointer ledger)
         mSourceMap.swap(sourceMap);
         mDestMap.swap(destMap);
     }
+    getApp().getLedgerMaster().newOrderBookDB();
 }
 
 void OrderBookDB::addOrderBook(const uint160& ci, const uint160& co,
diff --git a/src/ripple_app/paths/PathRequest.cpp b/src/ripple_app/paths/PathRequest.cpp
index f75a28101..f7c0a8d6a 100644
--- a/src/ripple_app/paths/PathRequest.cpp
+++ b/src/ripple_app/paths/PathRequest.cpp
@@ -256,6 +256,12 @@ Json::Value PathRequest::doStatus (const Json::Value&)
     return jvStatus;
 }
 
+void PathRequest::resetLevel (int l)
+{
+    if (iLastLevel > l)
+        iLastLevel = l;
+}
+
 bool PathRequest::doUpdate (RippleLineCache::ref cache, bool fast)
 {
     WriteLog (lsDEBUG, PathRequest) << iIdentifier << " update " << (fast ? "fast" : "normal");
@@ -403,7 +409,7 @@ bool PathRequest::doUpdate (RippleLineCache::ref cache, bool fast)
     return true;
 }
 
-void PathRequest::updateAll (Ledger::ref ledger, bool newOnly, CancelCallback shouldCancel)
+void PathRequest::updateAll (Ledger::ref ledger, bool newOnly, bool hasNew, CancelCallback shouldCancel)
 {
     std::set<wptr> requests;
 
@@ -433,6 +439,10 @@ void PathRequest::updateAll (Ledger::ref ledger, bool newOnly, CancelCallback sh
 
         if (pRequest)
         {
+            // Drop old requests level to get new ones done faster
+            if (hasNew)
+                pRequest->resetLevel(getConfig().PATH_SEARCH);
+
             if (newOnly && !pRequest->isNew ())
                 remove = false;
             else
diff --git a/src/ripple_app/paths/PathRequest.h b/src/ripple_app/paths/PathRequest.h
index 4d4ae87fd..2fc87658d 100644
--- a/src/ripple_app/paths/PathRequest.h
+++ b/src/ripple_app/paths/PathRequest.h
@@ -58,10 +58,11 @@ public:
 
     bool        doUpdate (const boost::shared_ptr<RippleLineCache>&, bool fast); // update jvStatus
 
-    static void updateAll (const boost::shared_ptr<Ledger>& ledger, bool newOnly, CancelCallback shouldCancel);
+    static void updateAll (const boost::shared_ptr<Ledger>& ledger, bool newOnly, bool hasNew, CancelCallback shouldCancel);
 
 private:
     void setValid ();
+    void resetLevel (int level);
     int parseJson (const Json::Value&, bool complete);
 
     typedef RippleRecursiveMutex LockType;