synchronization - cpp中的多线程难题

Question

void BalanceTransfer(Account &FromAccount, Account &ToAccount, double amount)
{
    FromAccount.Substract(amount);
    ToAccount.Add(amount);
    //What is the best way to protect this function if there are 100 threads calling this function for 1000's of accounts...
}

Answer 1

在每个帐户中都有一个互斥锁。在事务之前，锁定两个互斥锁（当然之后释放它们）。锁定顺序很重要；为避免死锁，您需要定义锁定顺序，例如始终首先锁定具有最低帐号的帐户。