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Use a uint256 for bnChainWork

Every block index entry currently requires a separately-allocated
CBigNum. By replacing them with uint256, it's just 32 bytes extra
in CBlockIndex itself.

This should save us a few megabytes in RAM, and less allocation
overhead.
tags/v0.15.1
Pieter Wuille 8 years ago
parent
commit
1657c4bc49
5 changed files with 48 additions and 36 deletions
  1. 5
    5
      contrib/test-patches/bitcoind-comparison.patch
  2. 1
    1
      src/bignum.h
  3. 25
    23
      src/main.cpp
  4. 7
    7
      src/main.h
  5. 10
    0
      src/uint256.h

+ 5
- 5
contrib/test-patches/bitcoind-comparison.patch View File

@@ -1,5 +1,5 @@
diff --git a/src/main.cpp b/src/main.cpp
index 8c115c2..1e70ff2 100644
diff --git a/contrib/test-patches/bitcoind-comparison.patch b/contrib/test-patches/bitcoind-comparison.patch
index 04a8618..519429a 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -31,8 +31,8 @@ CTxMemPool mempool;
@@ -12,7 +12,7 @@ index 8c115c2..1e70ff2 100644
+static CBigNum bnProofOfWorkLimit(~uint256(0) >> 1);
CBlockIndex* pindexGenesisBlock = NULL;
int nBestHeight = -1;
CBigNum bnBestChainWork = 0;
uint256 nBestChainWork = 0;
@@ -1055,7 +1055,7 @@ int64 static GetBlockValue(int nHeight, int64 nFees)
int64 nSubsidy = 50 * COIN;
@@ -22,7 +22,7 @@ index 8c115c2..1e70ff2 100644
return nSubsidy + nFees;
}
@@ -2706,9 +2706,9 @@ bool InitBlockIndex() {
@@ -2736,9 +2736,9 @@ bool InitBlockIndex() {
block.hashPrevBlock = 0;
block.hashMerkleRoot = block.BuildMerkleTree();
block.nVersion = 1;
@@ -35,7 +35,7 @@ index 8c115c2..1e70ff2 100644
if (fTestNet)
{
@@ -3007,7 +3007,7 @@ bool static AlreadyHave(const CInv& inv)
@@ -3024,7 +3024,7 @@ bool static AlreadyHave(const CInv& inv)
// The message start string is designed to be unlikely to occur in normal data.
// The characters are rarely used upper ASCII, not valid as UTF-8, and produce
// a large 4-byte int at any alignment.

+ 1
- 1
src/bignum.h View File

@@ -222,7 +222,7 @@ public:
BN_mpi2bn(pch, p - pch, this);
}

uint256 getuint256()
uint256 getuint256() const
{
unsigned int nSize = BN_bn2mpi(this, NULL);
if (nSize < 4)

+ 25
- 23
src/main.cpp View File

@@ -35,8 +35,8 @@ uint256 hashGenesisBlock("0x000000000019d6689c085ae165831e934ff763ae46a2a6c172b3
static CBigNum bnProofOfWorkLimit(~uint256(0) >> 32);
CBlockIndex* pindexGenesisBlock = NULL;
int nBestHeight = -1;
CBigNum bnBestChainWork = 0;
CBigNum bnBestInvalidWork = 0;
uint256 nBestChainWork = 0;
uint256 nBestInvalidWork = 0;
uint256 hashBestChain = 0;
CBlockIndex* pindexBest = NULL;
set<CBlockIndex*, CBlockIndexWorkComparator> setBlockIndexValid; // may contain all CBlockIndex*'s that have validness >=BLOCK_VALID_TRANSACTIONS, and must contain those who aren't failed
@@ -1191,20 +1191,20 @@ bool IsInitialBlockDownload()

void static InvalidChainFound(CBlockIndex* pindexNew)
{
if (pindexNew->bnChainWork > bnBestInvalidWork)
if (pindexNew->nChainWork > nBestInvalidWork)
{
bnBestInvalidWork = pindexNew->bnChainWork;
pblocktree->WriteBestInvalidWork(bnBestInvalidWork);
nBestInvalidWork = pindexNew->nChainWork;
pblocktree->WriteBestInvalidWork(CBigNum(nBestInvalidWork));
uiInterface.NotifyBlocksChanged();
}
printf("InvalidChainFound: invalid block=%s height=%d work=%s date=%s\n",
printf("InvalidChainFound: invalid block=%s height=%d log2_work=%.8g date=%s\n",
pindexNew->GetBlockHash().ToString().c_str(), pindexNew->nHeight,
pindexNew->bnChainWork.ToString().c_str(), DateTimeStrFormat("%Y-%m-%d %H:%M:%S",
log(pindexNew->nChainWork.getdouble())/log(2.0), DateTimeStrFormat("%Y-%m-%d %H:%M:%S",
pindexNew->GetBlockTime()).c_str());
printf("InvalidChainFound: current best=%s height=%d work=%s date=%s\n",
hashBestChain.ToString().c_str(), nBestHeight, bnBestChainWork.ToString().c_str(),
printf("InvalidChainFound: current best=%s height=%d log2_work=%.8g date=%s\n",
hashBestChain.ToString().c_str(), nBestHeight, log(nBestChainWork.getdouble())/log(2.0),
DateTimeStrFormat("%Y-%m-%d %H:%M:%S", pindexBest->GetBlockTime()).c_str());
if (pindexBest && bnBestInvalidWork > bnBestChainWork + pindexBest->GetBlockWork() * 6)
if (pindexBest && nBestInvalidWork > nBestChainWork + (pindexBest->GetBlockWork() * 6).getuint256())
printf("InvalidChainFound: Warning: Displayed transactions may not be correct! You may need to upgrade, or other nodes may need to upgrade.\n");
}

@@ -1230,7 +1230,7 @@ bool ConnectBestBlock(CValidationState &state) {
pindexNewBest = *it;
}

if (pindexNewBest == pindexBest || (pindexBest && pindexNewBest->bnChainWork == pindexBest->bnChainWork))
if (pindexNewBest == pindexBest || (pindexBest && pindexNewBest->nChainWork == pindexBest->nChainWork))
return true; // nothing to do

// check ancestry
@@ -1250,7 +1250,7 @@ bool ConnectBestBlock(CValidationState &state) {
break;
}

if (pindexBest == NULL || pindexTest->bnChainWork > pindexBest->bnChainWork)
if (pindexBest == NULL || pindexTest->nChainWork > pindexBest->nChainWork)
vAttach.push_back(pindexTest);

if (pindexTest->pprev == NULL || pindexTest->pnext != NULL) {
@@ -1858,11 +1858,11 @@ bool SetBestChain(CValidationState &state, CBlockIndex* pindexNew)
pindexBest = pindexNew;
pblockindexFBBHLast = NULL;
nBestHeight = pindexBest->nHeight;
bnBestChainWork = pindexNew->bnChainWork;
nBestChainWork = pindexNew->nChainWork;
nTimeBestReceived = GetTime();
nTransactionsUpdated++;
printf("SetBestChain: new best=%s height=%d work=%s tx=%lu date=%s progress=%f\n",
hashBestChain.ToString().c_str(), nBestHeight, bnBestChainWork.ToString().c_str(), (unsigned long)pindexNew->nChainTx,
printf("SetBestChain: new best=%s height=%d log2_work=%.8g tx=%lu date=%s progress=%f\n",
hashBestChain.ToString().c_str(), nBestHeight, log(nBestChainWork.getdouble())/log(2.0), (unsigned long)pindexNew->nChainTx,
DateTimeStrFormat("%Y-%m-%d %H:%M:%S", pindexBest->GetBlockTime()).c_str(),
Checkpoints::GuessVerificationProgress(pindexBest));

@@ -1915,7 +1915,7 @@ bool CBlock::AddToBlockIndex(CValidationState &state, const CDiskBlockPos &pos)
pindexNew->nHeight = pindexNew->pprev->nHeight + 1;
}
pindexNew->nTx = vtx.size();
pindexNew->bnChainWork = (pindexNew->pprev ? pindexNew->pprev->bnChainWork : 0) + pindexNew->GetBlockWork();
pindexNew->nChainWork = (pindexNew->pprev ? pindexNew->pprev->nChainWork : 0) + pindexNew->GetBlockWork().getuint256();
pindexNew->nChainTx = (pindexNew->pprev ? pindexNew->pprev->nChainTx : 0) + pindexNew->nTx;
pindexNew->nFile = pos.nFile;
pindexNew->nDataPos = pos.nPos;
@@ -2537,7 +2537,7 @@ bool static LoadBlockIndexDB()

boost::this_thread::interruption_point();

// Calculate bnChainWork
// Calculate nChainWork
vector<pair<int, CBlockIndex*> > vSortedByHeight;
vSortedByHeight.reserve(mapBlockIndex.size());
BOOST_FOREACH(const PAIRTYPE(uint256, CBlockIndex*)& item, mapBlockIndex)
@@ -2549,7 +2549,7 @@ bool static LoadBlockIndexDB()
BOOST_FOREACH(const PAIRTYPE(int, CBlockIndex*)& item, vSortedByHeight)
{
CBlockIndex* pindex = item.second;
pindex->bnChainWork = (pindex->pprev ? pindex->pprev->bnChainWork : 0) + pindex->GetBlockWork();
pindex->nChainWork = (pindex->pprev ? pindex->pprev->nChainWork : 0) + pindex->GetBlockWork().getuint256();
pindex->nChainTx = (pindex->pprev ? pindex->pprev->nChainTx : 0) + pindex->nTx;
if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_TRANSACTIONS && !(pindex->nStatus & BLOCK_FAILED_MASK))
setBlockIndexValid.insert(pindex);
@@ -2561,8 +2561,10 @@ bool static LoadBlockIndexDB()
if (pblocktree->ReadBlockFileInfo(nLastBlockFile, infoLastBlockFile))
printf("LoadBlockIndexDB(): last block file info: %s\n", infoLastBlockFile.ToString().c_str());

// Load bnBestInvalidWork, OK if it doesn't exist
// Load nBestInvalidWork, OK if it doesn't exist
CBigNum bnBestInvalidWork;
pblocktree->ReadBestInvalidWork(bnBestInvalidWork);
nBestInvalidWork = bnBestInvalidWork.getuint256();

// Check whether we need to continue reindexing
bool fReindexing = false;
@@ -2579,7 +2581,7 @@ bool static LoadBlockIndexDB()
return true;
hashBestChain = pindexBest->GetBlockHash();
nBestHeight = pindexBest->nHeight;
bnBestChainWork = pindexBest->bnChainWork;
nBestChainWork = pindexBest->nChainWork;

// set 'next' pointers in best chain
CBlockIndex *pindex = pindexBest;
@@ -2675,8 +2677,8 @@ void UnloadBlockIndex()
setBlockIndexValid.clear();
pindexGenesisBlock = NULL;
nBestHeight = 0;
bnBestChainWork = 0;
bnBestInvalidWork = 0;
nBestChainWork = 0;
nBestInvalidWork = 0;
hashBestChain = 0;
pindexBest = NULL;
}
@@ -2953,7 +2955,7 @@ string GetWarnings(string strFor)
}

// Longer invalid proof-of-work chain
if (pindexBest && bnBestInvalidWork > bnBestChainWork + pindexBest->GetBlockWork() * 6)
if (pindexBest && nBestInvalidWork > nBestChainWork + (pindexBest->GetBlockWork() * 6).getuint256())
{
nPriority = 2000;
strStatusBar = strRPC = _("Warning: Displayed transactions may not be correct! You may need to upgrade, or other nodes may need to upgrade.");

+ 7
- 7
src/main.h View File

@@ -77,8 +77,8 @@ extern std::set<CBlockIndex*, CBlockIndexWorkComparator> setBlockIndexValid;
extern uint256 hashGenesisBlock;
extern CBlockIndex* pindexGenesisBlock;
extern int nBestHeight;
extern CBigNum bnBestChainWork;
extern CBigNum bnBestInvalidWork;
extern uint256 nBestChainWork;
extern uint256 nBestInvalidWork;
extern uint256 hashBestChain;
extern CBlockIndex* pindexBest;
extern unsigned int nTransactionsUpdated;
@@ -1619,7 +1619,7 @@ public:
unsigned int nUndoPos;

// (memory only) Total amount of work (expected number of hashes) in the chain up to and including this block
CBigNum bnChainWork;
uint256 nChainWork;

// Number of transactions in this block.
// Note: in a potential headers-first mode, this number cannot be relied upon
@@ -1648,7 +1648,7 @@ public:
nFile = 0;
nDataPos = 0;
nUndoPos = 0;
bnChainWork = 0;
nChainWork = 0;
nTx = 0;
nChainTx = 0;
nStatus = 0;
@@ -1669,7 +1669,7 @@ public:
nFile = 0;
nDataPos = 0;
nUndoPos = 0;
bnChainWork = 0;
nChainWork = 0;
nTx = 0;
nChainTx = 0;
nStatus = 0;
@@ -1793,8 +1793,8 @@ public:
struct CBlockIndexWorkComparator
{
bool operator()(CBlockIndex *pa, CBlockIndex *pb) {
if (pa->bnChainWork > pb->bnChainWork) return false;
if (pa->bnChainWork < pb->bnChainWork) return true;
if (pa->nChainWork > pb->nChainWork) return false;
if (pa->nChainWork < pb->nChainWork) return true;

if (pa->GetBlockHash() < pb->GetBlockHash()) return false;
if (pa->GetBlockHash() > pb->GetBlockHash()) return true;

+ 10
- 0
src/uint256.h View File

@@ -55,6 +55,16 @@ public:
return ret;
}

double getdouble() const
{
double ret = 0.0;
double fact = 1.0;
for (int i = 0; i < WIDTH; i++) {
ret += fact * pn[i];
fact *= 4294967296.0;
}
return ret;
}

base_uint& operator=(uint64 b)
{

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