多線程拼圖在CPP

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

在每個帳戶互斥。在交易之前，鎖定兩個互斥體（當然，之後再釋放它們）。鎖定順序很重要;爲避免死鎖，您需要定義的鎖定順序，例如，始終先用最低的賬號鎖定賬戶。