html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue
https://github.com/pydata/xarray/issues/4804#issuecomment-760114285,https://api.github.com/repos/pydata/xarray/issues/4804,760114285,MDEyOklzc3VlQ29tbWVudDc2MDExNDI4NQ==,5700886,2021-01-14T10:44:19Z,2021-01-14T10:44:19Z,CONTRIBUTOR,"I'd also add that https://github.com/pydata/xarray/blob/master/xarray/core/computation.py#L1320_L1330 which is essentially
```python
((x - x.mean()) * (y - y.mean())).mean()
```
is inferior to
```python
(x * y).mean() - x.mean() * y.mean()
```
because it leads to Dask holding all chunks of `x` in memory (see, e.g., https://github.com/dask/dask/issues/6674 for details).","{""total_count"": 2, ""+1"": 2, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,785329941