Merge #7056: Save last db read

8504867 Save the last unnecessary database read (Alex Morcos)
This commit is contained in:
Wladimir J. van der Laan 2016-01-22 14:15:45 +01:00 committed by Alexander Block
parent 4ecbedbe74
commit 996f5103a0
3 changed files with 11 additions and 13 deletions

View File

@ -117,11 +117,17 @@ CCoinsModifier CCoinsViewCache::ModifyCoins(const uint256 &txid) {
return CCoinsModifier(*this, ret.first, cachedCoinUsage);
}
CCoinsModifier CCoinsViewCache::ModifyNewCoins(const uint256 &txid) {
// ModifyNewCoins has to know whether the new outputs its creating are for a
// coinbase or not. If they are for a coinbase, it can not mark them as fresh.
// This is to ensure that the historical duplicate coinbases before BIP30 was
// in effect will still be properly overwritten when spent.
CCoinsModifier CCoinsViewCache::ModifyNewCoins(const uint256 &txid, bool coinbase) {
assert(!hasModifier);
std::pair<CCoinsMap::iterator, bool> ret = cacheCoins.insert(std::make_pair(txid, CCoinsCacheEntry()));
ret.first->second.coins.Clear();
ret.first->second.flags = CCoinsCacheEntry::FRESH;
if (!coinbase) {
ret.first->second.flags = CCoinsCacheEntry::FRESH;
}
ret.first->second.flags |= CCoinsCacheEntry::DIRTY;
return CCoinsModifier(*this, ret.first, 0);
}

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@ -435,7 +435,7 @@ public:
* would not properly overwrite the first coinbase of the pair. Simultaneous modifications
* are not allowed.
*/
CCoinsModifier ModifyNewCoins(const uint256 &txid);
CCoinsModifier ModifyNewCoins(const uint256 &txid, bool coinbase);
/**
* Push the modifications applied to this cache to its base.

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@ -1445,17 +1445,9 @@ void UpdateCoins(const CTransaction& tx, CValidationState &state, CCoinsViewCach
undo.nVersion = coins->nVersion;
}
}
// add outputs
inputs.ModifyNewCoins(tx.GetHash())->FromTx(tx, nHeight);
}
else {
// add outputs for coinbase tx
// In this case call the full ModifyCoins which will do a database
// lookup to be sure the coins do not already exist otherwise we do not
// know whether to mark them fresh or not. We want the duplicate coinbases
// before BIP30 to still be properly overwritten.
inputs.ModifyCoins(tx.GetHash())->FromTx(tx, nHeight);
}
// add outputs
inputs.ModifyNewCoins(tx.GetHash(), tx.IsCoinBase())->FromTx(tx, nHeight);
}
void UpdateCoins(const CTransaction& tx, CValidationState &state, CCoinsViewCache &inputs, int nHeight)