issues: 1523232313

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
1523232313 PR_kwDOAMm_X85G2q5I 7426 Add lazy backend ASV test 14371165 closed 0     1 2023-01-06T22:01:26Z 2023-01-12T16:00:05Z 2023-01-11T18:56:25Z MEMBER   0 pydata/xarray/pulls/7426

This tests xr.open_dataset without any slow file reading that can quickly become the majority of the performance time.

Related to #7374.

Timings for the new ASV-tests: ```

[ 50.85%] ··· dataset_io.IOReadCustomEngine.time_open_dataset ok [ 50.85%] ··· ======== ============ chunks
-------- ------------ None 265±4ms
{} 1.17±0.02s ======== ============ [ 54.69%] ··· dataset_io.IOReadSingleFile.time_read_dataset ok [ 54.69%] ··· ========= ============= ============= -- chunks
--------- --------------------------- engine None {}
========= ============= ============= scipy 4.81±0.1ms 6.65±0.01ms netcdf4 8.41±0.08ms 10.9±0.2ms ========= ============= ============= ``` From the IOReadCustomEngine test we can see that chunking datasets with many variables (2000+) is considerably slower.

 
{
    "url": "https://api.github.com/repos/pydata/xarray/issues/7426/reactions",
    "total_count": 0,
    "+1": 0,
    "-1": 0,
    "laugh": 0,
    "hooray": 0,
    "confused": 0,
    "heart": 0,
    "rocket": 0,
    "eyes": 0
}
     13221727 pull

Links from other tables