Create new BlockPolicyEstimator for fee estimates

This class groups transactions that have been confirmed in blocks into buckets, based on either their fee or their priority.  Then for each bucket, the class calculates what percentage of the transactions were confirmed within various numbers of blocks.  It does this by keeping an exponentially decaying moving history for each bucket and confirm block count of the percentage of transactions in that bucket that were confirmed within that number of blocks.

-Eliminate txs which didn't have all inputs available at entry from fee/pri calcs

-Add dynamic breakpoints and tracking of confirmation delays in mempool transactions

-Remove old CMinerPolicyEstimator and CBlockAverage code

-New smartfees.py

-Pass a flag to the estimation code, using IsInitialBlockDownload as a proxy for when we are still catching up and we shouldn't be counting how many blocks it takes for transactions to be included.

-Add a policyestimator unit test

1 files changed, 13 insertions, 7 deletions

diff --git a/src/txmempool.h b/src/txmempool.h
index 0732af67e6..7271a5f603 100644
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -43,10 +43,11 @@ private:
     int64_t nTime; //! Local time when entering the mempool
     double dPriority; //! Priority when entering the mempool
     unsigned int nHeight; //! Chain height when entering the mempool
+    bool hadNoDependencies; //! Not dependent on any other txs when it entered the mempool
 
 public:
     CTxMemPoolEntry(const CTransaction& _tx, const CAmount& _nFee,
-                    int64_t _nTime, double _dPriority, unsigned int _nHeight);
+                    int64_t _nTime, double _dPriority, unsigned int _nHeight, bool poolHasNoInputsOf = false);
     CTxMemPoolEntry();
     CTxMemPoolEntry(const CTxMemPoolEntry& other);
 
@@ -56,9 +57,10 @@ public:
     size_t GetTxSize() const { return nTxSize; }
     int64_t GetTime() const { return nTime; }
     unsigned int GetHeight() const { return nHeight; }
+    bool WasClearAtEntry() const { return hadNoDependencies; }
 };
 
-class CMinerPolicyEstimator;
+class CBlockPolicyEstimator;
 
 /** An inpoint - a combination of a transaction and an index n into its vin */
 class CInPoint
@@ -88,9 +90,8 @@ class CTxMemPool
 private:
     bool fSanityCheck; //! Normally false, true if -checkmempool or -regtest
     unsigned int nTransactionsUpdated;
-    CMinerPolicyEstimator* minerPolicyEstimator;
+    CBlockPolicyEstimator* minerPolicyEstimator;
 
-    CFeeRate minRelayFee; //! Passed to constructor to avoid dependency on main
     uint64_t totalTxSize; //! sum of all mempool tx' byte sizes
 
 public:
@@ -111,17 +112,22 @@ public:
     void check(const CCoinsViewCache *pcoins) const;
     void setSanityCheck(bool _fSanityCheck) { fSanityCheck = _fSanityCheck; }
 
-    bool addUnchecked(const uint256& hash, const CTxMemPoolEntry &entry);
+    bool addUnchecked(const uint256& hash, const CTxMemPoolEntry &entry, bool fCurrentEstimate = true);
     void remove(const CTransaction &tx, std::list<CTransaction>& removed, bool fRecursive = false);
     void removeCoinbaseSpends(const CCoinsViewCache *pcoins, unsigned int nMemPoolHeight);
     void removeConflicts(const CTransaction &tx, std::list<CTransaction>& removed);
     void removeForBlock(const std::vector<CTransaction>& vtx, unsigned int nBlockHeight,
-                        std::list<CTransaction>& conflicts);
+                        std::list<CTransaction>& conflicts, bool fCurrentEstimate = true);
     void clear();
     void queryHashes(std::vector<uint256>& vtxid);
     void pruneSpent(const uint256& hash, CCoins &coins);
     unsigned int GetTransactionsUpdated() const;
     void AddTransactionsUpdated(unsigned int n);
+    /**
+     * Check that none of this transactions inputs are in the mempool, and thus
+     * the tx is not dependent on other mempool transactions to be included in a block.
+     */
+    bool HasNoInputsOf(const CTransaction& tx) const;
 
     /** Affect CreateNewBlock prioritisation of transactions */
     void PrioritiseTransaction(const uint256 hash, const std::string strHash, double dPriorityDelta, const CAmount& nFeeDelta);
@@ -139,7 +145,7 @@ public:
         return totalTxSize;
     }
 
-    bool exists(uint256 hash)
+    bool exists(uint256 hash) const
     {
         LOCK(cs);
         return (mapTx.count(hash) != 0);