System configuration¶
Overview¶
You can find the necessary information to run circuits on a target system or simulator in two ways:
On the upper left corner of the screen, click the Application switcher (
), select Compute resources to view the Compute resources page, then click the Systems or Simulators tab.Use Qiskit commands. This information includes details about the physical (real system) or simulator setup of the system, as well as configurable properties, such as the maximum number of circuits that can be executed in a single job. The configuration, along with configuration details of control electronics (if any), can be used to assign a version number to a system.
System configuration values¶
The following is a subset of system configuration values available in IBM Quantum and from Qiskit.
These values are shown on both the Systems and Simulators tabs of the Compute resources page and the details page for each system.
Name - The unique name assigned to a specific quantum system or simulator. Backends hosted on IBM Cloud® have names that begin with
ibmq_*. All quantum systems are given a city name, e.g.,ibmq_johannesburg. This name does not indicate where the actual quantum system is hosted. They are named after IBM locations around the world.Qubits - The number of qubits in a system. For physical quantum systems, this is the number of physical qubits in the device. For simulators, this number need not be uniquely defined, and instead can depend on the simulation method and/or the amount of memory available.
QV - Quantum volume. This value measures the performance of gate-based quantum computers, regardless of their underlying technology.
CLOPS - CLOPS, or circuit layer operations per second, is a measure of how many layers of a QV circuit a QPU (quantum processing unit) can execute per unit of time. Find more information about this metric in the paper called Quality, Speed, and Scale: three key attributes to measure the performance of near-term quantum computers.
Status - The system status.
Total pending jobs - The total number of jobs that you have submitted to this system.
Processor type - Reflects the system topology and indicates the approximate qubit count.
Features - Additional information about the system, such as whether it can be reserved and whether it supports pulse inputs.
Additional information available on the details page for each system
To access the details page, click the name of the system on the Compute resources page.
Version - The version number of a system in the form
major.minor.revision. See System versioning for details on how this number is assigned.Calibration data (Available for systems only) - Download the calibration data as a .csv file or click the arrow to display the Topology diagram, Individual qubit readout graph, or the Calibration data table. You can customize the data that is shown, depending on the view you have open. For example, on the Topology diagram, you can choose the data you want to see for connections and qubits. The colored bars associated with the diagram or graph indicate the range that is shown, with the average value marked. The color maximum and minimum change depending on the system.
Topology diagram or coupling map - A diagram that indicates the pairs of qubits that support two-qubit gate operations between them. This is also called the coupling map or connectivity. Qubits are represented as circles and the supported two-qubit gate operations are displayed as lines connecting the qubits.
Individual qubit properties - Shows the selected property for each qubit on the system. You can view the frequency, T1, T2, Anharmonicity, probability measurements, error rates, and so on.
Your access providers - Providers that you can use. Click the arrow on the right to expand or collapse this section. For each provider, you can see the following information:
Max shots - The maximum number of times you can execute a single circuit on a system. The number of shots taken determines the precision of the output probability distribution over repeated executions.
Max circuits - The maximum number of quantum circuits that you can submit to this system at one time.
Max qubits per pulse gate - The maximum number of qubit arguments allowed to a gate.
Max channels per pulse gate - The maximum number of channels you can refer to within a pulse schedule. Typically each qubit is associated with a drive channel, a measure channel, an acquisition channel, and then auxiliary control channels for things like cross resonance.
Usage - Click the link to see the jobs that you have run on this system.
View system configuration¶
View system configuration values by selecting a system on the Systems tab of the Compute resources page. The three tabs in the Calibration data section let you choose how to view the calibration data; the Map view tab is automatically selected.
An expanded card for a sample system.¶
Click the download icon in the upper right of any tab to download a CSV file of calibration data.
The Graph view tab.¶
The Table view tab.¶
View system configuration in Qiskit¶
In Qiskit, obtain the system configuration information via:
or graphically using:
import qiskit.providers.ibmq.jupyter
IBMQ.load_account()
provider = IBMQ.get_provider(group='open', project='main')
system = provider.get_backend('ibmq_vigo')
system
