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/pull/5704#issuecomment-1528693660,https://api.github.com/repos/pydata/xarray/issues/5704,1528693660,IC_kwDOAMm_X85bHgOc,14371165,2023-04-29T06:56:37Z,2023-04-29T06:58:26Z,MEMBER,"Those issues indeed has to be fixed if opening files lazily is the _only_ option for xarray.
But xarray could also accept that `chunks=None` will (for now) load all the files to memory. If that's ok we can merge this now I believe.
I suspect there are a few in-memory users out there that could make use of this.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,970245117
https://github.com/pydata/xarray/pull/5704#issuecomment-1527695510,https://api.github.com/repos/pydata/xarray/issues/5704,1527695510,IC_kwDOAMm_X85bDsiW,35968931,2023-04-28T14:57:54Z,2023-04-28T14:57:54Z,MEMBER,For the benefit of anyone else reading this having come from https://github.com/pydata/xarray/issues/7792 or similar questions - see https://github.com/pydata/xarray/issues/4628 and https://github.com/pydata/xarray/issues/5081 to see what needs to be done. Also see discussion in https://github.com/pydata/xarray/issues/6807 for non-dask lazy backends.,"{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,970245117
https://github.com/pydata/xarray/pull/5704#issuecomment-903442749,https://api.github.com/repos/pydata/xarray/issues/5704,903442749,IC_kwDOAMm_X8412XE9,14371165,2021-08-23T04:55:06Z,2021-08-23T04:55:06Z,MEMBER,"That the arrays would be loaded into memory is what you would expect if a user insists on using `chunks=None` right?
I just changed the default value to {}. So now it will behave as it did previously but with the possibility to load into memory for whatever reason you might have with small files.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,970245117
https://github.com/pydata/xarray/pull/5704#issuecomment-903347552,https://api.github.com/repos/pydata/xarray/issues/5704,903347552,IC_kwDOAMm_X8411_1g,1217238,2021-08-22T23:27:45Z,2021-08-22T23:27:45Z,MEMBER,"The reason why `open_mfdataset` _always_ uses dask is because otherwise it would not be lazy: the netCDF files would be immediately read into memory as NumPy arrays. `open_dataset` uses Xarray's own internal lazy indexing machinery, but that machinery doesn't (yet) support lazy concatenation or broadcasting, so it doesn't suffice for `open_mfdataset`.
We certainly _could_ make a similar change to this, but I would not do so by default. Or I would add support for lazy concatenation into xarray's lazy indexing, and then we could slowly roll out a breaking change (with appropriate FutureWarning, etc).","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,970245117
https://github.com/pydata/xarray/pull/5704#issuecomment-903176445,https://api.github.com/repos/pydata/xarray/issues/5704,903176445,IC_kwDOAMm_X8411WD9,14371165,2021-08-21T21:06:38Z,2021-08-21T21:06:38Z,MEMBER,"One way of making this less controversial is to also change the default value of `chunks` from `None` to `{}` here
https://github.com/pydata/xarray/blob/48a9dbe7d8dc2361bc985dd9fb1193a26135b310/xarray/backends/api.py#L696
Then the default settings will behave the same as before. Although it's still not consistent with `xr.open_dataset`s default parameters which mfdataset is just a thin wrapper around.
It is indeed bad practice to use dicts as default value but not completely uncommon, see for example:
https://github.com/pydata/xarray/blob/48a9dbe7d8dc2361bc985dd9fb1193a26135b310/xarray/core/dataset.py#L2111","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,970245117
https://github.com/pydata/xarray/pull/5704#issuecomment-898356703,https://api.github.com/repos/pydata/xarray/issues/5704,898356703,IC_kwDOAMm_X841i9Xf,14371165,2021-08-13T10:23:23Z,2021-08-13T10:27:30Z,MEMBER,"A lot of failing tests but they seem to just assume that open_mfdataset always returns dask arrays by default. Probably as simple as adding chunks={} in all these tests, but this is quite a breaking change.
Do you know the reason why `chunks=chunks or {}` is used in `open_mfdataset`, @aurghs?","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,970245117