Update best practices page (quantumlib#8243)

Updates the best practices doc to reflect some changes since the
document was written.

Author: eliottrosenberg

docs/google/best_practices.ipynb

@@ -96,6 +96,7 @@
     "This guide is split into three parts:\n",
     "*  Getting your circuit to run\n",
     "*  Making it run faster\n",
+    "*  Running it without keeping your laptop online\n",
     "*  Lowering error"
    ]
   },
@@ -112,12 +113,24 @@
     "gates will immediately cause a circuit to fail.\n",
     "\n",
     "Validating a circuit with a device, such as\n",
-    "`cg.Sycamore.validate_circuit(circuit)` will test a lot of these\n",
+    "`cg.Willow105.validate_circuit(circuit)` will test a lot of these\n",
     "conditions.  Calling the `validate_circuit` function will work with any\n",
     "device, including those retrieved directly from the API using the\n",
     "[engine object](./specification.md#conversion-to-cirq.device), which can help\n",
     "identify any qubits used in the circuit that have been disabled on the actual\n",
-    "device."
+    "device. Sometimes, a pair of qubits may not have a gate calibrated between them\n",
+    "even though the device object shows them as coupled. One way to see which pairs\n",
+    "of adjacent qubits do not support gates between them is by checking the two-qubit\n",
+    "XEB metrics, which can be found in the web UI\n",
+    "([engine.quantumai.google](https://quantumai.engine.google)), where unsupported\n",
+    "pairs of qubits will show as grey and be missing two-qubit metrics. These pairs of\n",
+    "qubits will also be missing metrics in `engine.get_config(...).calibration`.\n",
+    "\n",
+    "Circuits containing gates other than CZ and single-qubit microwave gates may require\n",
+    "special internal calibration. For example, if you intend to use cphase gates, physical\n",
+    "Z gates, analog circuits, etc., you should discuss this with the Google support team\n",
+    "to make sure the necessary calibrations and benchmarks are performed. Circuits containing\n",
+    "classically-conditioned operations are not currently supported."
    ]
   },
   {
@@ -250,7 +263,9 @@
     "id": "0e58b5ded5cb"
    },
    "source": [
-    "### Use sweeps when possible\n",
+    "### Use sweeps or batches when possible\n",
+    "\n",
+    "#### Sweeps:\n",
     "\n",
     "Round trip network time to and from the engine typically adds latency on the order of a second\n",
     "to the overall computation time.  Reducing the number of trips and allowing the engine to\n",
@@ -315,16 +330,15 @@
     "id": "114fb6c6b766"
    },
    "source": [
-    "### Use batches if sweeps are not possible\n",
+    "#### Batches:\n",
     "\n",
     "The sampler has a method called `run_batch()` that can be used to send multiple\n",
     "circuits in a single request.  This can be used to increase the efficiency\n",
     "of your program so that more repetitions are completed per second.\n",
     "\n",
-    "The circuits that are grouped into the same batch must\n",
-    "measure the same qubits and have the same number of repetitions for each\n",
-    "circuit.  Otherwise, the circuits will not be batched together\n",
-    "on the device, and there will be no gain in efficiency."
+    "By default, `run_batch` will create one job per circuit. It is also possible to\n",
+    "pack multiple circuits into a job by specifying `jobs_per_batch` when loading the\n",
+    "sampler using [`cirq_google.engine.ProcessorSampler(..., jobs_per_batch=...)`](https://quantumai.google/reference/python/cirq_google/engine/ProcessorSampler)."
    ]
   },
   {
@@ -371,6 +385,37 @@
     "print(list(flat_sweep.param_tuples()))"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "id": "3e442c11d381"
+   },
+   "source": [
+    "## Running circuits without keeping your laptop online\n",
+    "\n",
+    "One can create an\n",
+    "[`EngineProgram`](https://quantumai.google/reference/python/cirq_google/engine/EngineProgram)\n",
+    "using\n",
+    "[`engine.create_program`](https://quantumai.google/reference/python/cirq_google/engine/Engine#create_program).\n",
+    "You can pass either a circuit or a list of circuits to this method, and you\n",
+    "can optionally specify a program ID, description, and labels. After running\n",
+    "this, the program should appear in the\n",
+    "[\"Programs\" tab](https://console.cloud.google.com/quantum/programs) of the older web UI.\n",
+    "\n",
+    "You can then run a program using\n",
+    "[`program.run()`](https://quantumai.google/reference/python/cirq_google/engine/EngineProgram#run)\n",
+    "or\n",
+    "[`program.run_sweep()`](https://quantumai.google/reference/python/cirq_google/engine/EngineProgram#run_sweep),\n",
+    "which returns an [`EngineJob`](https://quantumai.google/reference/python/cirq_google/engine/EngineJob),\n",
+    "which you can query for its status (`job.status()`) and its results (`job.results()`).\n",
+    "Jobs can be named by specifying a `job_id` at the `program.run()` or `program.run_sweep()` step and can be retrived later\n",
+    "using `job = engine.get_program(program_id).get_job(job_id)`. Jobs appear in the\n",
+    "[jobs tab](https://console.cloud.google.com/quantum/jobs) of the older UI and the programs/jobs\n",
+    "tab of the [new UI](https://engine.quantumai.google/program). Corresponding calibration metrics\n",
+    "can be viewed using `job.get_config().calibration`. See the\n",
+    "[calibration metrics tutorial](https://quantumai.google/cirq/google/calibration) for more details."
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {
@@ -413,8 +458,7 @@
     "measuring all qubits with a single gate or by adding\n",
     "the measurement gate after all optimizers have run.\n",
     "\n",
-    "Currently, only terminal measurements are supported by the hardware.  If you\n",
-    "absolutely need intermediate measurements for your application, reach out to\n",
+    "If you need intermediate measurements for your application, reach out to\n",
     "your Google sponsor to see if they can help devise a proper circuit using\n",
     "intermediate measurements.\n",
     "\n",
@@ -425,7 +469,8 @@
     "[Spin Echo](https://en.wikipedia.org/wiki/Spin_echo) into your circuit onto\n",
     "qubits that have long idle periods, such as a pair\n",
     "of involutions, such as two successive Pauli Y gates, will generally increase\n",
-    "performance of the circuit.\n",
+    "performance of the circuit. This can be done using\n",
+    "[`cirq.add_dynamical_decoupling`](https://quantumai.google/reference/python/cirq/add_dynamical_decoupling).\n",
     "\n",
     "Be aware that this should be done after calling\n",
     "`cirq.optimize_for_target_gateset`, since this function will 'optimize'\n",
@@ -470,13 +515,7 @@
     "calibration procedure.  These metrics can be used as a baseline to evaluate\n",
     "circuit performance or identify outliers to avoid.  This data can be inspected\n",
     "programmatically by retrieving metrics from the [API](calibration.md) or\n",
-    "[visually by applying a cirq.Heatmap](../tutorials/google/visualizing_calibration_metrics.ipynb)\n",
-    "to that data or by using the built-in\n",
-    "heatmaps in the Cloud console page for the processor.  Note that, since this\n",
-    "data is only taken during calibration (e.g. at most daily), drifts and other\n",
-    "concerns may affect the values significantly, so these metrics should only be\n",
-    "used as a first approximation.  There is no substitute for actually running characterizations\n",
-    "on the device.\n",
+    "using the [web UI](https://engine.quantumai.google).\n",
     "*   Loschmidt echo:  Running a small circuit on a string of qubits and then\n",
     "applying the circuit's inverse can be used as a quick but effective way to\n",
     "judge qubit quality.  See\n",