From 22dcc023d085615906ed4b2f37213df5ffb1e236 Mon Sep 17 00:00:00 2001
From: Nguyen Sy Thanh Son <thanhson1085@gmail.com>
Date: Thu, 31 Jan 2019 04:20:26 +0000
Subject: [PATCH] set min gas price for tx

---
 core/tx_pool.go | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/core/tx_pool.go b/core/tx_pool.go
index e80c74c797..c4a777a0fb 100644
--- a/core/tx_pool.go
+++ b/core/tx_pool.go
@@ -81,6 +81,8 @@ var (
 
 	ErrZeroGasPrice = errors.New("zero gas price")
 
+	ErrUnderMinGasPrice = errors.New("under min gas price")
+
 	ErrDuplicateSpecialTransaction = errors.New("duplicate a special transaction")
 
 	ErrMinDeploySMC = errors.New("smart contract creation cost is under allowance")
@@ -621,6 +623,11 @@ func (pool *TxPool) validateTx(tx *types.Transaction, local bool) error {
 		if tx.GasPrice().Cmp(new(big.Int).SetInt64(0)) == 0 {
 			return ErrZeroGasPrice
 		}
+
+		// under min gas price
+		if tx.GasPrice().Cmp(new(big.Int).SetInt64(common.MinGasPrice)) < 0 {
+			return ErrUnderMinGasPrice
+		}
 	}
 
 	minGasDeploySMC := new(big.Int).Mul(new(big.Int).SetUint64(10), new(big.Int).SetUint64(params.Ether))