id,node_id,number,title,user,state,locked,assignee,milestone,comments,created_at,updated_at,closed_at,author_association,active_lock_reason,draft,pull_request,body,reactions,performed_via_github_app,state_reason,repo,type
1554036799,PR_kwDOAMm_X85IYHUz,7472,Avoid in-memory broadcasting when converting to_dask_dataframe,14371165,closed,0,,,1,2023-01-24T00:15:01Z,2023-01-26T17:00:24Z,2023-01-26T17:00:23Z,MEMBER,,0,pydata/xarray/pulls/7472,"Turns out that there's a call to `.set_dims` that forces a broadcast on the numpy coordinates.
<!-- Feel free to remove check-list items aren't relevant to your change -->

- [x] Closes  #6811
- [x] Tests added, see #7474.
- [x] User visible changes (including notable bug fixes) are documented in `whats-new.rst`


Debugging script:

<details>

```python
import dask.array as da
import xarray as xr
import numpy as np

chunks = 5000

# I have to restart the pc if running with this:
# dim1_sz = 100_000
# dim2_sz = 100_000

# Does not crash when using the following constants, >5 gig RAM increase though:
dim1_sz = 40_000
dim2_sz = 40_000

x = da.random.random((dim1_sz, dim2_sz), chunks=chunks)

ds = xr.Dataset(
    {
        ""x"": xr.DataArray(
            data=x,
            dims=[""dim1"", ""dim2""],
            coords={""dim1"": np.arange(0, dim1_sz), ""dim2"": np.arange(0, dim2_sz)},
        )
    }
)

# with dask.config.set(**{""array.slicing.split_large_chunks"": True}):
df = ds.to_dask_dataframe()
print(df)
```

</details>","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/7472/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,pull
1555497796,PR_kwDOAMm_X85Ic_wm,7474,Add benchmarks for to_dataframe and to_dask_dataframe,14371165,closed,0,,,1,2023-01-24T18:48:26Z,2023-01-24T21:00:39Z,2023-01-24T20:13:30Z,MEMBER,,0,pydata/xarray/pulls/7474,Related to #7472.,"{""url"": ""https://api.github.com/repos/pydata/xarray/issues/7474/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,pull