Various performance tweaks to CCoinsView

* Pass txid's to CCoinsView functions by reference instead of by value
* Add a method to swap CCoins, and use it in some places to avoid a
  allocating copy + destruct.
* Optimize CCoinsViewCache::FetchCoins to do only a single search
  through the backing map.
This commit is contained in:
Pieter Wuille 2013-01-20 18:05:34 +01:00
parent 71eccdeaff
commit f369d02c51
4 changed files with 47 additions and 37 deletions

View File

@ -171,9 +171,9 @@ void static ResendWalletTransactions()
// CCoinsView implementations
//
bool CCoinsView::GetCoins(uint256 txid, CCoins &coins) { return false; }
bool CCoinsView::SetCoins(uint256 txid, const CCoins &coins) { return false; }
bool CCoinsView::HaveCoins(uint256 txid) { return false; }
bool CCoinsView::GetCoins(const uint256 &txid, CCoins &coins) { return false; }
bool CCoinsView::SetCoins(const uint256 &txid, const CCoins &coins) { return false; }
bool CCoinsView::HaveCoins(const uint256 &txid) { return false; }
CBlockIndex *CCoinsView::GetBestBlock() { return NULL; }
bool CCoinsView::SetBestBlock(CBlockIndex *pindex) { return false; }
bool CCoinsView::BatchWrite(const std::map<uint256, CCoins> &mapCoins, CBlockIndex *pindex) { return false; }
@ -181,9 +181,9 @@ bool CCoinsView::GetStats(CCoinsStats &stats) { return false; }
CCoinsViewBacked::CCoinsViewBacked(CCoinsView &viewIn) : base(&viewIn) { }
bool CCoinsViewBacked::GetCoins(uint256 txid, CCoins &coins) { return base->GetCoins(txid, coins); }
bool CCoinsViewBacked::SetCoins(uint256 txid, const CCoins &coins) { return base->SetCoins(txid, coins); }
bool CCoinsViewBacked::HaveCoins(uint256 txid) { return base->HaveCoins(txid); }
bool CCoinsViewBacked::GetCoins(const uint256 &txid, CCoins &coins) { return base->GetCoins(txid, coins); }
bool CCoinsViewBacked::SetCoins(const uint256 &txid, const CCoins &coins) { return base->SetCoins(txid, coins); }
bool CCoinsViewBacked::HaveCoins(const uint256 &txid) { return base->HaveCoins(txid); }
CBlockIndex *CCoinsViewBacked::GetBestBlock() { return base->GetBestBlock(); }
bool CCoinsViewBacked::SetBestBlock(CBlockIndex *pindex) { return base->SetBestBlock(pindex); }
void CCoinsViewBacked::SetBackend(CCoinsView &viewIn) { base = &viewIn; }
@ -192,7 +192,7 @@ bool CCoinsViewBacked::GetStats(CCoinsStats &stats) { return base->GetStats(stat
CCoinsViewCache::CCoinsViewCache(CCoinsView &baseIn, bool fDummy) : CCoinsViewBacked(baseIn), pindexTip(NULL) { }
bool CCoinsViewCache::GetCoins(uint256 txid, CCoins &coins) {
bool CCoinsViewCache::GetCoins(const uint256 &txid, CCoins &coins) {
if (cacheCoins.count(txid)) {
coins = cacheCoins[txid];
return true;
@ -204,29 +204,30 @@ bool CCoinsViewCache::GetCoins(uint256 txid, CCoins &coins) {
return false;
}
std::map<uint256,CCoins>::iterator CCoinsViewCache::FetchCoins(uint256 txid) {
std::map<uint256,CCoins>::iterator it = cacheCoins.find(txid);
if (it != cacheCoins.end())
std::map<uint256,CCoins>::iterator CCoinsViewCache::FetchCoins(const uint256 &txid) {
std::map<uint256,CCoins>::iterator it = cacheCoins.lower_bound(txid);
if (it != cacheCoins.end() && it->first == txid)
return it;
CCoins tmp;
if (!base->GetCoins(txid,tmp))
return it;
std::pair<std::map<uint256,CCoins>::iterator,bool> ret = cacheCoins.insert(std::make_pair(txid, tmp));
return ret.first;
return cacheCoins.end();
std::map<uint256,CCoins>::iterator ret = cacheCoins.insert(it, std::make_pair(txid, CCoins()));
tmp.swap(ret->second);
return ret;
}
CCoins &CCoinsViewCache::GetCoins(uint256 txid) {
CCoins &CCoinsViewCache::GetCoins(const uint256 &txid) {
std::map<uint256,CCoins>::iterator it = FetchCoins(txid);
assert(it != cacheCoins.end());
return it->second;
}
bool CCoinsViewCache::SetCoins(uint256 txid, const CCoins &coins) {
bool CCoinsViewCache::SetCoins(const uint256 &txid, const CCoins &coins) {
cacheCoins[txid] = coins;
return true;
}
bool CCoinsViewCache::HaveCoins(uint256 txid) {
bool CCoinsViewCache::HaveCoins(const uint256 &txid) {
return FetchCoins(txid) != cacheCoins.end();
}
@ -263,7 +264,7 @@ unsigned int CCoinsViewCache::GetCacheSize() {
It does not check for spendings by memory pool transactions. */
CCoinsViewMemPool::CCoinsViewMemPool(CCoinsView &baseIn, CTxMemPool &mempoolIn) : CCoinsViewBacked(baseIn), mempool(mempoolIn) { }
bool CCoinsViewMemPool::GetCoins(uint256 txid, CCoins &coins) {
bool CCoinsViewMemPool::GetCoins(const uint256 &txid, CCoins &coins) {
if (base->GetCoins(txid, coins))
return true;
if (mempool.exists(txid)) {
@ -274,7 +275,7 @@ bool CCoinsViewMemPool::GetCoins(uint256 txid, CCoins &coins) {
return false;
}
bool CCoinsViewMemPool::HaveCoins(uint256 txid) {
bool CCoinsViewMemPool::HaveCoins(const uint256 &txid) {
return mempool.exists(txid) || base->HaveCoins(txid);
}

View File

@ -918,6 +918,15 @@ public:
void Cleanup() {
while (vout.size() > 0 && vout.back().IsNull())
vout.pop_back();
if (vout.empty())
std::vector<CTxOut>().swap(vout);
}
void swap(CCoins &to) {
std::swap(to.fCoinBase, fCoinBase);
to.vout.swap(vout);
std::swap(to.nHeight, nHeight);
std::swap(to.nVersion, nVersion);
}
// equality test
@ -2077,14 +2086,14 @@ class CCoinsView
{
public:
// Retrieve the CCoins (unspent transaction outputs) for a given txid
virtual bool GetCoins(uint256 txid, CCoins &coins);
virtual bool GetCoins(const uint256 &txid, CCoins &coins);
// Modify the CCoins for a given txid
virtual bool SetCoins(uint256 txid, const CCoins &coins);
virtual bool SetCoins(const uint256 &txid, const CCoins &coins);
// Just check whether we have data for a given txid.
// This may (but cannot always) return true for fully spent transactions
virtual bool HaveCoins(uint256 txid);
virtual bool HaveCoins(const uint256 &txid);
// Retrieve the block index whose state this CCoinsView currently represents
virtual CBlockIndex *GetBestBlock();
@ -2110,9 +2119,9 @@ protected:
public:
CCoinsViewBacked(CCoinsView &viewIn);
bool GetCoins(uint256 txid, CCoins &coins);
bool SetCoins(uint256 txid, const CCoins &coins);
bool HaveCoins(uint256 txid);
bool GetCoins(const uint256 &txid, CCoins &coins);
bool SetCoins(const uint256 &txid, const CCoins &coins);
bool HaveCoins(const uint256 &txid);
CBlockIndex *GetBestBlock();
bool SetBestBlock(CBlockIndex *pindex);
void SetBackend(CCoinsView &viewIn);
@ -2131,9 +2140,9 @@ public:
CCoinsViewCache(CCoinsView &baseIn, bool fDummy = false);
// Standard CCoinsView methods
bool GetCoins(uint256 txid, CCoins &coins);
bool SetCoins(uint256 txid, const CCoins &coins);
bool HaveCoins(uint256 txid);
bool GetCoins(const uint256 &txid, CCoins &coins);
bool SetCoins(const uint256 &txid, const CCoins &coins);
bool HaveCoins(const uint256 &txid);
CBlockIndex *GetBestBlock();
bool SetBestBlock(CBlockIndex *pindex);
bool BatchWrite(const std::map<uint256, CCoins> &mapCoins, CBlockIndex *pindex);
@ -2141,7 +2150,7 @@ public:
// Return a modifiable reference to a CCoins. Check HaveCoins first.
// Many methods explicitly require a CCoinsViewCache because of this method, to reduce
// copying.
CCoins &GetCoins(uint256 txid);
CCoins &GetCoins(const uint256 &txid);
// Push the modifications applied to this cache to its base.
// Failure to call this method before destruction will cause the changes to be forgotten.
@ -2151,7 +2160,7 @@ public:
unsigned int GetCacheSize();
private:
std::map<uint256,CCoins>::iterator FetchCoins(uint256 txid);
std::map<uint256,CCoins>::iterator FetchCoins(const uint256 &txid);
};
/** CCoinsView that brings transactions from a memorypool into view.
@ -2163,8 +2172,8 @@ protected:
public:
CCoinsViewMemPool(CCoinsView &baseIn, CTxMemPool &mempoolIn);
bool GetCoins(uint256 txid, CCoins &coins);
bool HaveCoins(uint256 txid);
bool GetCoins(const uint256 &txid, CCoins &coins);
bool HaveCoins(const uint256 &txid);
};
/** Global variable that points to the active CCoinsView (protected by cs_main) */

View File

@ -22,17 +22,17 @@ void static BatchWriteHashBestChain(CLevelDBBatch &batch, const uint256 &hash) {
CCoinsViewDB::CCoinsViewDB(size_t nCacheSize, bool fMemory, bool fWipe) : db(GetDataDir() / "coins", nCacheSize, fMemory, fWipe) {
}
bool CCoinsViewDB::GetCoins(uint256 txid, CCoins &coins) {
bool CCoinsViewDB::GetCoins(const uint256 &txid, CCoins &coins) {
return db.Read(make_pair('c', txid), coins);
}
bool CCoinsViewDB::SetCoins(uint256 txid, const CCoins &coins) {
bool CCoinsViewDB::SetCoins(const uint256 &txid, const CCoins &coins) {
CLevelDBBatch batch;
BatchWriteCoins(batch, txid, coins);
return db.WriteBatch(batch);
}
bool CCoinsViewDB::HaveCoins(uint256 txid) {
bool CCoinsViewDB::HaveCoins(const uint256 &txid) {
return db.Exists(make_pair('c', txid));
}

View File

@ -16,9 +16,9 @@ protected:
public:
CCoinsViewDB(size_t nCacheSize, bool fMemory = false, bool fWipe = false);
bool GetCoins(uint256 txid, CCoins &coins);
bool SetCoins(uint256 txid, const CCoins &coins);
bool HaveCoins(uint256 txid);
bool GetCoins(const uint256 &txid, CCoins &coins);
bool SetCoins(const uint256 &txid, const CCoins &coins);
bool HaveCoins(const uint256 &txid);
CBlockIndex *GetBestBlock();
bool SetBestBlock(CBlockIndex *pindex);
bool BatchWrite(const std::map<uint256, CCoins> &mapCoins, CBlockIndex *pindex);