On testnet I am analyzing the following transaction https://testnet.etherscan.io/tx/0x7b111a37998b25116b1a6962d393253bf09613dd083b420ec24ffc9a28bc74b6 having this attributes:
Gas: 90000 and Gas Used By Transaction: 21000
I guess 21000 is the actual fee applied to this tx, but what is Gas: 90000 then?
I am a bit confused because when querying this tx through json-rpc on my geth node using eth_getTransactionByHash method I got this result:
gas => 0x15f90 = 90000
but there is no field gasUsed or similar. So it seems there is no way to find out actual tx fee, right?
How can I get gasUsed value for a tx using json-rpc calls?