From 0dd06b2515cd4d1f0be4dcf9060e34f3b9abde76 Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Tue, 25 Nov 2014 12:33:43 +0100
Subject: [PATCH] Delay writing block indexes in invalidate/reconsider

---
 src/main.cpp | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/src/main.cpp b/src/main.cpp
index eeef513528..5695c8ba51 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2140,17 +2140,13 @@ bool InvalidateBlock(CValidationState& state, CBlockIndex *pindex) {
 
     // Mark the block itself as invalid.
     pindex->nStatus |= BLOCK_FAILED_VALID;
-    if (!pblocktree->WriteBlockIndex(CDiskBlockIndex(pindex))) {
-        return state.Abort("Failed to update block index");
-    }
+    setDirtyBlockIndex.insert(pindex);
     setBlockIndexCandidates.erase(pindex);
 
     while (chainActive.Contains(pindex)) {
         CBlockIndex *pindexWalk = chainActive.Tip();
         pindexWalk->nStatus |= BLOCK_FAILED_CHILD;
-        if (!pblocktree->WriteBlockIndex(CDiskBlockIndex(pindexWalk))) {
-            return state.Abort("Failed to update block index");
-        }
+        setDirtyBlockIndex.insert(pindexWalk);
         setBlockIndexCandidates.erase(pindexWalk);
         // ActivateBestChain considers blocks already in chainActive
         // unconditionally valid already, so force disconnect away from it.
@@ -2183,9 +2179,7 @@ bool ReconsiderBlock(CValidationState& state, CBlockIndex *pindex) {
     while (it != mapBlockIndex.end()) {
         if (!it->second->IsValid() && it->second->GetAncestor(nHeight) == pindex) {
             it->second->nStatus &= ~BLOCK_FAILED_MASK;
-            if (!pblocktree->WriteBlockIndex(CDiskBlockIndex(pindex))) {
-                return state.Abort("Failed to update block index");
-            }
+            setDirtyBlockIndex.insert(it->second);
             if (it->second->IsValid(BLOCK_VALID_TRANSACTIONS) && it->second->nChainTx && setBlockIndexCandidates.value_comp()(chainActive.Tip(), it->second)) {
                 setBlockIndexCandidates.insert(it->second);
             }
@@ -2199,9 +2193,9 @@ bool ReconsiderBlock(CValidationState& state, CBlockIndex *pindex) {
 
     // Remove the invalidity flag from all ancestors too.
     while (pindex != NULL) {
-        pindex->nStatus &= ~BLOCK_FAILED_MASK;
-        if (!pblocktree->WriteBlockIndex(CDiskBlockIndex(pindex))) {
-            return state.Abort("Failed to update block index");
+        if (pindex->nStatus & BLOCK_FAILED_MASK) {
+            pindex->nStatus &= ~BLOCK_FAILED_MASK;
+            setDirtyBlockIndex.insert(pindex);
         }
         pindex = pindex->pprev;
     }