Add ancestor tracking to mempool

This implements caching of ancestor state to each mempool entry, similar to
descendant tracking, but also including caching sigops-with-ancestors (as that
metric will be helpful to future code that implements better transaction
selection in CreatenewBlock).

1 files changed, 43 insertions, 6 deletions

diff --git a/src/txmempool.h b/src/txmempool.h
index b1b6645a06..0db3d5bd27 100644
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -80,6 +80,12 @@ private:
     uint64_t nSizeWithDescendants;  //! ... and size
     CAmount nModFeesWithDescendants;  //! ... and total fees (all including us)
 
+    // Analogous statistics for ancestor transactions
+    uint64_t nCountWithAncestors;
+    uint64_t nSizeWithAncestors;
+    CAmount nModFeesWithAncestors;
+    unsigned int nSigOpCountWithAncestors;
+
 public:
     CTxMemPoolEntry(const CTransaction& _tx, const CAmount& _nFee,
                     int64_t _nTime, double _entryPriority, unsigned int _entryHeight,
@@ -103,7 +109,9 @@ public:
     size_t DynamicMemoryUsage() const { return nUsageSize; }
 
     // Adjusts the descendant state, if this entry is not dirty.
-    void UpdateState(int64_t modifySize, CAmount modifyFee, int64_t modifyCount);
+    void UpdateDescendantState(int64_t modifySize, CAmount modifyFee, int64_t modifyCount);
+    // Adjusts the ancestor state
+    void UpdateAncestorState(int64_t modifySize, CAmount modifyFee, int64_t modifyCount, int modifySigOps);
     // Updates the fee delta used for mining priority score, and the
     // modified fees with descendants.
     void UpdateFeeDelta(int64_t feeDelta);
@@ -113,6 +121,11 @@ public:
     CAmount GetModFeesWithDescendants() const { return nModFeesWithDescendants; }
 
     bool GetSpendsCoinbase() const { return spendsCoinbase; }
+
+    uint64_t GetCountWithAncestors() const { return nCountWithAncestors; }
+    uint64_t GetSizeWithAncestors() const { return nSizeWithAncestors; }
+    CAmount GetModFeesWithAncestors() const { return nModFeesWithAncestors; }
+    unsigned int GetSigOpCountWithAncestors() const { return nSigOpCountWithAncestors; }
 };
 
 // Helpers for modifying CTxMemPool::mapTx, which is a boost multi_index.
@@ -123,12 +136,28 @@ struct update_descendant_state
     {}
 
     void operator() (CTxMemPoolEntry &e)
-        { e.UpdateState(modifySize, modifyFee, modifyCount); }
+        { e.UpdateDescendantState(modifySize, modifyFee, modifyCount); }
+
+    private:
+        int64_t modifySize;
+        CAmount modifyFee;
+        int64_t modifyCount;
+};
+
+struct update_ancestor_state
+{
+    update_ancestor_state(int64_t _modifySize, CAmount _modifyFee, int64_t _modifyCount, int _modifySigOps) :
+        modifySize(_modifySize), modifyFee(_modifyFee), modifyCount(_modifyCount), modifySigOps(_modifySigOps)
+    {}
+
+    void operator() (CTxMemPoolEntry &e)
+        { e.UpdateAncestorState(modifySize, modifyFee, modifyCount, modifySigOps); }
 
     private:
         int64_t modifySize;
         CAmount modifyFee;
         int64_t modifyCount;
+        int modifySigOps;
 };
 
 struct update_fee_delta
@@ -440,8 +469,12 @@ public:
 public:
     /** Remove a set of transactions from the mempool.
      *  If a transaction is in this set, then all in-mempool descendants must
-     *  also be in the set.*/
-    void RemoveStaged(setEntries &stage);
+     *  also be in the set, unless this transaction is being removed for being
+     *  in a block.
+     *  Set updateDescendants to true when removing a tx that was in a block, so
+     *  that any in-mempool descendants have their ancestor state updated.
+     */
+    void RemoveStaged(setEntries &stage, bool updateDescendants);
 
     /** When adding transactions from a disconnected block back to the mempool,
      *  new mempool entries may have children in the mempool (which is generally
@@ -551,8 +584,12 @@ private:
             const std::set<uint256> &setExclude);
     /** Update ancestors of hash to add/remove it as a descendant transaction. */
     void UpdateAncestorsOf(bool add, txiter hash, setEntries &setAncestors);
-    /** For each transaction being removed, update ancestors and any direct children. */
-    void UpdateForRemoveFromMempool(const setEntries &entriesToRemove);
+    /** Set ancestor state for an entry */
+    void UpdateEntryForAncestors(txiter it, const setEntries &setAncestors);
+    /** For each transaction being removed, update ancestors and any direct children.
+      * If updateDescendants is true, then also update in-mempool descendants'
+      * ancestor state. */
+    void UpdateForRemoveFromMempool(const setEntries &entriesToRemove, bool updateDescendants);
     /** Sever link between specified transaction and direct children. */
     void UpdateChildrenForRemoval(txiter entry);