What happened?

Let's take this sample netcdf file.

Observe that the memory has not been cleared even after deleting the ds.

Code ```bash import os import psutil import xarray as xr from memory_profiler import profile

@profile def main(): path = 'ECMWF_ERA-40_subset.nc' print(f"Before opening file: {psutil.Process(os.getpid()).memory_info().rss / 1024 ** 2} MiB") ds = xr.open_dataset(path) del ds print(f"After opening file: {psutil.Process(os.getpid()).memory_info().rss / 1024 ** 2} MiB")

if name == 'main': print(f"Start: {psutil.Process(os.getpid()).memory_info().rss / 1024 ** 2} MiB") main() print(f"End: {psutil.Process(os.getpid()).memory_info().rss / 1024 ** 2} MiB") ```

Console logs ```bash Start: 186.5859375 MiB Before opening file: 187.25 MiB After opening file: 308.09375 MiB Filename: temp.py

Line # Mem usage Increment Occurrences Line Contents

 6    187.2 MiB    187.2 MiB           1   @profile
 7                                         def main():
 8    187.2 MiB      0.0 MiB           1       path = 'ECMWF_ERA-40_subset.nc'
 9    187.2 MiB      0.0 MiB           1       print(f"Before opening file: {psutil.Process(os.getpid()).memory_info().rss / 1024 ** 2} MiB")
10    308.1 MiB    120.8 MiB           1       ds = xr.open_dataset(path)
11    308.1 MiB      0.0 MiB           1       del ds
12    308.1 MiB      0.0 MiB           1       print(f"After opening file: {psutil.Process(os.getpid()).memory_info().rss / 1024 ** 2} MiB")

End: 308.09375 MiB ```

I am using xarray==0.20.2and gdal==3.5.1. Sister issue: https://github.com/ecmwf/cfgrib/issues/325#issuecomment-1363011917

What did you expect to happen?

Ideally, memory consumed by the xarray dataset should be released when the dataset is closed/deleted.

Minimal Complete Verifiable Example

No response

MVCE confirmation

• [ ] Minimal example — the example is as focused as reasonably possible to demonstrate the underlying issue in xarray.
• [ ] Complete example — the example is self-contained, including all data and the text of any traceback.
• [ ] Verifiable example — the example copy & pastes into an IPython prompt or Binder notebook, returning the result.
• [ ] New issue — a search of GitHub Issues suggests this is not a duplicate.

Relevant log output

No response

Anything else we need to know?

No response

Environment

INSTALLED VERSIONS ------------------ commit: None python: 3.7.12 | packaged by conda-forge | (default, Oct 26 2021, 06:08:53) [GCC 9.4.0] python-bits: 64 OS: Linux OS-release: 4.19.0-22-cloud-amd64 machine: x86_64 processor: byteorder: little LC_ALL: None LANG: C.UTF-8 LOCALE: ('en_US', 'UTF-8') libhdf5: 1.12.2 libnetcdf: 4.8.1 xarray: 0.20.2 pandas: 1.3.5 numpy: 1.19.5 scipy: 1.7.3 netCDF4: 1.6.0 pydap: None h5netcdf: 1.0.2 h5py: 3.7.0 Nio: None zarr: 2.12.0 cftime: 1.6.1 nc_time_axis: None PseudoNetCDF: None rasterio: 1.2.10 cfgrib: 0.9.10.1 iris: None bottleneck: None dask: 2022.02.0 distributed: 2022.02.0 matplotlib: 3.5.2 cartopy: 0.20.3 seaborn: 0.11.2 numbagg: None fsspec: 2022.7.1 cupy: None pint: None sparse: None setuptools: 59.8.0 pip: 22.2.2 conda: 22.9.0 pytest: None IPython: 7.33.0 sphinx: None