issues: 653442225

This data as json

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
653442225 MDU6SXNzdWU2NTM0NDIyMjU= 4209 `xr.save_mfdataset()` doesn't honor `compute=False` argument 13301940 open 0     4 2020-07-08T16:40:11Z 2022-04-09T01:25:56Z   MEMBER      

What happened:

While using xr.save_mfdataset() function with compute=False I noticed that the function returns a dask.delayed object, but it doesn't actually defer the computation i.e. it actually writes datasets right away.

What you expected to happen:

I expect the datasets to be written when I explicitly call .compute() on the returned delayed object.

Minimal Complete Verifiable Example:

```python In [2]: import xarray as xr

In [3]: ds = xr.tutorial.open_dataset('rasm', chunks={})

In [4]: ds Out[4]: <xarray.Dataset> Dimensions: (time: 36, x: 275, y: 205) Coordinates: * time (time) object 1980-09-16 12:00:00 ... 1983-08-17 00:00:00 xc (y, x) float64 dask.array<chunksize=(205, 275), meta=np.ndarray> yc (y, x) float64 dask.array<chunksize=(205, 275), meta=np.ndarray> Dimensions without coordinates: x, y Data variables: Tair (time, y, x) float64 dask.array<chunksize=(36, 205, 275), meta=np.ndarray> Attributes: title: /workspace/jhamman/processed/R1002RBRxaaa01a/l... institution: U.W. source: RACM R1002RBRxaaa01a output_frequency: daily output_mode: averaged convention: CF-1.4 references: Based on the initial model of Liang et al., 19... comment: Output from the Variable Infiltration Capacity... nco_openmp_thread_number: 1 NCO: "4.6.0" history: Tue Dec 27 14:15:22 2016: ncatted -a dimension...

In [5]: path = "test.nc"

In [7]: ls -ltrh test.nc ls: cannot access test.nc: No such file or directory

In [8]: tasks = xr.save_mfdataset(datasets=[ds], paths=[path], compute=False)

In [9]: tasks Out[9]: Delayed('list-aa0b52e0-e909-4e65-849f-74526d137542')

In [10]: ls -ltrh test.nc -rw-r--r-- 1 abanihi ncar 14K Jul 8 10:29 test.nc ```

Anything else we need to know?:

Environment:

Output of <tt>xr.show_versions()</tt> ```python INSTALLED VERSIONS ------------------ commit: None python: 3.7.6 | packaged by conda-forge | (default, Jun 1 2020, 18:57:50) [GCC 7.5.0] python-bits: 64 OS: Linux OS-release: 3.10.0-693.21.1.el7.x86_64 machine: x86_64 processor: x86_64 byteorder: little LC_ALL: en_US.UTF-8 LANG: en_US.UTF-8 LOCALE: en_US.UTF-8 libhdf5: 1.10.5 libnetcdf: 4.7.4 xarray: 0.15.1 pandas: 0.25.3 numpy: 1.18.5 scipy: 1.5.0 netCDF4: 1.5.3 pydap: None h5netcdf: None h5py: 2.10.0 Nio: None zarr: None cftime: 1.2.0 nc_time_axis: 1.2.0 PseudoNetCDF: None rasterio: None cfgrib: None iris: None bottleneck: None dask: 2.20.0 distributed: 2.20.0 matplotlib: 3.2.1 cartopy: None seaborn: None numbagg: None setuptools: 49.1.0.post20200704 pip: 20.1.1 conda: None pytest: None IPython: 7.16.1 sphinx: None ``` 
{
    "url": "https://api.github.com/repos/pydata/xarray/issues/4209/reactions",
    "total_count": 0,
    "+1": 0,
    "-1": 0,
    "laugh": 0,
    "hooray": 0,
    "confused": 0,
    "heart": 0,
    "rocket": 0,
    "eyes": 0
}
     13221727 issue

Links from other tables