This question already has an answer here:
While doing any transaction in private network, is it necessary for one node to keep on mining?.
I was trying to implement to deploy smart contract and transact in ethereum private network with the help of web3j java library. When there was no mining happening, my java transaction code was error out and it was saying transaction exceeds time limit of 600 seconds. But when I started mining and run the program, it was successful. But because of these two process, my system became very slow.
What is the reason behind these scenario? Any suggestion?