Merge #617: [Wallet] Adjust staking properties to lower orphan rates.

4c862f2 Lower stake hashdrift to 30 seconds. (presstab)
355e2d3 Update zPIV stake set more frequently. (presstab)

Tree-SHA512: fcbfeb23bdf5e84c38d64780b97cd0a3f6d7ecb630b2b2e7ba13daf2538d691409be70d889b418b3165c79c0ec0bcc8080dd1aec072d559bf77b1e9093af75e7

src/kernel.cpp

@@ -315,7 +315,7 @@ bool Stake(CStakeInput* stakeInput, unsigned int nBits, unsigned int nTimeBlockF
  bool fSuccess = false;
  unsigned int nTryTime = 0;
  int nHeightStart = chainActive.Height();
- int nHashDrift = 45;
+ int nHashDrift = 30;
  CDataStream ssUniqueID = stakeInput->GetUniqueness();
  CAmount nValueIn = stakeInput->GetValue();
  for (int i = 0; i < nHashDrift; i++) //iterate the hashing

src/wallet.cpp

@@ -2115,9 +2115,15 @@ bool CWallet::SelectStakeCoins(std::list<std::unique_ptr<CStakeInput> >& listInp
 
  //zPIV
  if (GetBoolArg("-zpivstake", true) && chainActive.Height() > Params().Zerocoin_Block_V2_Start() && !IsSporkActive(SPORK_16_ZEROCOIN_MAINTENANCE_MODE)) {
- //Add zPIV
- set<CMintMeta> setMints = zpivTracker->ListMints(true, true, true);
+ //Only update zPIV set once per update interval
+ bool fUpdate = false;
+ static int64_t nTimeLastUpdate = 0;
+ if (GetAdjustedTime() - nTimeLastUpdate > nStakeSetUpdateTime) {
+ fUpdate = true;
+ nTimeLastUpdate = GetAdjustedTime();
+ }
 
+ set<CMintMeta> setMints = zpivTracker->ListMints(true, true, fUpdate);
  for (auto meta : setMints) {
  if (meta.hashStake == 0) {
  CZerocoinMint mint;
@@ -2944,16 +2950,10 @@ bool CWallet::CreateCoinStake(const CKeyStore& keystore, unsigned int nBits, int
  if (nBalance > 0 && nBalance <= nReserveBalance)
  return false;
 
- // Initialize as static and don't update the set on every run of CreateCoinStake() in order to lighten resource use
- static int nLastStakeSetUpdate = 0;
- static list<std::unique_ptr<CStakeInput> > listInputs;
- if (GetTime() - nLastStakeSetUpdate > nStakeSetUpdateTime) {
- listInputs.clear();
- if (!SelectStakeCoins(listInputs, nBalance - nReserveBalance))
- return false;
-
- nLastStakeSetUpdate = GetTime();
- }
+ // Get the list of stakable inputs
+ std::list<std::unique_ptr<CStakeInput> > listInputs;
+ if (!SelectStakeCoins(listInputs, nBalance - nReserveBalance))
+ return false;
 
  if (listInputs.empty())
  return false;
@@ -3084,7 +3084,6 @@ bool CWallet::CreateCoinStake(const CKeyStore& keystore, unsigned int nBits, int
  }
 
  // Successfully generated coinstake
- nLastStakeSetUpdate = 0; //this will trigger stake set to repopulate next round
  return true;
 }