diff --git a/eth/gasprice/gasprice.go b/eth/gasprice/gasprice.go
index 54325692c6..05c0131ba7 100644
--- a/eth/gasprice/gasprice.go
+++ b/eth/gasprice/gasprice.go
@@ -132,9 +132,10 @@ func (gpo *Oracle) SuggestPrice(ctx context.Context) (*big.Int, error) {
 		}
 	}
 	price := lastPrice
-	if len(blockPrices) > 0 {
+	blockPricesSize = len(blockPrices)
+	if blockPricesSize > 0 {
 		sort.Sort(bigIntArray(blockPrices))
-		price = blockPrices[(len(blockPrices)-1)*gpo.percentile/100]
+		price = blockPrices[(blockPricesSize-1)*gpo.percentile/100]
 	}
 	if price.Cmp(maxPrice) > 0 {
 		price = new(big.Int).Set(maxPrice)