I have been trying to run a circuit on ibmq_16_melbourne. But the result shows ERROR_RUNNING_JOB. The run status says: 'Circuit runtime is greater than the device repetition rate [8020]'.

Here are a few circuit details:

Size (total number of gates): 14137
Depth: 7836
Qubits: 14
Shots: 64

Gate count: [('u1', 7506), ('cx', 5850), ('u2', 678), ('x', 73), ('cswap', 18), ('h', 6), ('measure', 6)]

It runs fine on the qasm_simulator. I could not find how to deal with this kind of error. Can some tell what does it mean and how to fix it?


1 Answer 1


This error means that the circuit is too deep, you need to reduce the depth of the circuit in order to get it to run. This means that you need to reduce the number of gates you are using.

If you have not already, I would suggest running it through the transpiler using a higher optimization level before you run it to see if this reduces the gate count. You can do this by doing execute(your_circuit, backend, optimization_level=3)

Alternatively, you can continue running the circuit on the simulator, but add a NoiseModel to make it more like a run on a real device. There is more information about how to do that here.

  • $\begingroup$ I tried what you said but it gave me the same error. I ran the circuit through the transpiler for backend = 'ibmq_16_melbourne' and optimization_level = 3. The size and depth of the optimized circuit are 23058 and 12300 respectively both of which are greater that the size and depth of the original circuit. Is this possible? Or am I missing something? $\endgroup$ Apr 24, 2020 at 12:38
  • $\begingroup$ I am afraid those are both much too high to run on the real backends because they will take longer to execute than the given time for the execution of one circuit. I would recommend modifying your circuit to reduce its size and depth $\endgroup$
    – met927
    Apr 24, 2020 at 12:53
  • $\begingroup$ If you would like to run the circuit on the simulator with realistic noise you can use a NoiseModel. There is an explanation about how to do that here qiskit.org/textbook/ch-quantum-hardware/… $\endgroup$
    – met927
    Apr 24, 2020 at 13:04
  • 1
    $\begingroup$ The simulator with the noise model was really helpful. Thanks for that..! $\endgroup$ Apr 25, 2020 at 5:50
  • $\begingroup$ Great, glad I could help! Would you mind accepting the answer if it has answered your question? I have added the bit about NoiseModels :) $\endgroup$
    – met927
    Apr 26, 2020 at 13:17

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