adding FakeGeneva

[1ucian0]

This PRs adds FakeGeneva based on ibm_geneva.

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[mtreinish]

This lgtm, the only thing missing I think is adding it to the fake provider so that the tests will pick it up. See: https://github.com/Qiskit/qiskit-terra/blob/main/qiskit/providers/fake_provider/fake_provider.py#L130

[1ucian0]

the only thing missing I think is adding it to the fake provider so that the tests will pick it up

done in ca4d827 . thanks!

[coveralls]

Pull Request Test Coverage Report for Build 3092203514

• 12 of 12 (100.0%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.003%) to 84.399%

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Totals
Change from base Build 3092200812:	0.003%
Covered Lines:	59276
Relevant Lines:	70233

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💛 - Coveralls

[HuangJunye]

Looks great! The only thing I want to comment is the ordering. Shouldn't Geneva go before Guadalupe?

[1ucian0]

Looks great! The only thing I want to comment is the ordering. Shouldn't Geneva go before Guadalupe?

Thanks! Fixed in 6cf67f5

[HuangJunye]

Thanks for fixing the order. LGTM!

[nonhermitian]

Before accepting these kind of PRs, one should check that the snapshot is actually a good one. Here some of the 2Q gates have errors of 1, eg.:

"qubits": [16, 14], "gate": "cx", "parameters": [{"date": "2022-07-11T17:50:35.854518+02:00", "name": "gate_error", "unit": "", "value": 1}

[1ucian0]

good catch. I will update update_fake_backends.py to warning about it.

[HuangJunye]

In addition to #8331, should we also add a test for checking the gate error and other qubit properties?

[1ucian0]

Before accepting these kind of PRs, one should check that the snapshot is actually a good one. Here some of the 2Q gates have errors of 1, eg.:

Like ibm_washington, exploratory systems seems to have this kind of issues. I will keep an eye checking for new updates. I still think there is value in having it as a fakebackend, even with errors=1. Alternative, i can remove the properties from geneva.

[nonhermitian]

So the difference is that Geneva is a new 27Q system that probably still has some kinks to work out. You are grabbing a snapshot of it when there are 7 CX gates (13%) with faulty calibrations. If anything you should either wait a bit (there is no rush), or grab a cal that is at least as good as one can get given the device history. For example, the following timestamps will give you calibrations with only 2 bad CX gates:

2022-06-25 06:06:47.365299
2022-06-24 06:06:48.326497
2022-06-23 06:06:49.151597

With respect to Washington, the first system of its family, it has 284 CX gates in the coupling map, and it is possible to get calibrations for that system with only 4 bad cx gates (2%). So selecting a calibration that has 13% bad cx gates on a processor family that has been around for a couple of years seems a bit off to me. Perhaps one can just wait until close to the next release date and see how things pan out before adding a snapshot?

[1ucian0]

awesome! thanks for the tip @nonhermitian

Updating this PR with the calibration from 2022-06-24 23:00:30+02:00

ibm_geneva
==========
Gate errors == 1:
 * cx 20, 19
 * cx 16, 14
╒══════════════╤═════════════════════════════════╤═════════════════════════════════════╕
│   error == 1 │  new 2022-06-24 23:00:30+02:00  │  current 2022-07-12 14:40:53+02:00  │
╞══════════════╪═════════════════════════════════╪═════════════════════════════════════╡
│     cx error │          2/56 (3.57%)           │            7/56 (12.50%)            │
├──────────────┼─────────────────────────────────┼─────────────────────────────────────┤
│    all gates │          2/191 (1.05%)          │            7/191 (3.66%)            │
╘══════════════╧═════════════════════════════════╧═════════════════════════════════════╛

[1ucian0]

This one should be done too @mtreinish