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/7657#issuecomment-1483092471,https://api.github.com/repos/pydata/xarray/issues/7657,1483092471,IC_kwDOAMm_X85YZjH3,14808389,2023-03-24T16:35:17Z,2023-03-24T16:37:45Z,MEMBER,"depends on the test, I guess. Most of them are related to one of the netcdf backends (not sure which, the tests don't specify that), `test_dataarray_compute` just checks `_in_memory` (no I/O involved), and the pydap tests use netcdf underneath. So I'd say the issue is with one of the netcdf backends (`netcdf4`, as that's first in the priority list).
I've also seen a drastic reduction in performance with HDF5 1.12.2 (both netcdf4 and h5netcdf) on one of my colleague's datasets, so maybe that's much more visible on a mac? That doesn't explain the slow `test_dataarray_compute`, though.
Do we isolate the dask scheduler in any way? I assume that makes use of the builtin (non-`distributed`) scheduler?","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1635470616
https://github.com/pydata/xarray/pull/7657#issuecomment-1483049816,https://api.github.com/repos/pydata/xarray/issues/7657,1483049816,IC_kwDOAMm_X85YZYtY,14808389,2023-03-24T16:04:28Z,2023-03-24T16:04:28Z,MEMBER,"> Is it for a particular backend?
Not sure I understand. Can you elaborate, please?","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1635470616
https://github.com/pydata/xarray/pull/7657#issuecomment-1481344641,https://api.github.com/repos/pydata/xarray/issues/7657,1481344641,IC_kwDOAMm_X85YS4aB,14808389,2023-03-23T14:56:17Z,2023-03-23T14:56:17Z,MEMBER,"since the `macos` 3.11 CI is not required, I'm tempted to merge this now, and continue to debug elsewhere.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1635470616
https://github.com/pydata/xarray/pull/7657#issuecomment-1480905116,https://api.github.com/repos/pydata/xarray/issues/7657,1480905116,IC_kwDOAMm_X85YRNGc,14808389,2023-03-23T10:00:54Z,2023-03-23T10:05:37Z,MEMBER,"I guess that means that the CPUs of the windows and macos runners are just slow, or there's other tasks that get prioritized, or something. All of this results in the tests being pretty flaky, so I'm not sure what we can do about it. I don't have access to any, but maybe someone with a mac could try to reproduce?
In any case, I'll increase the timeout a bit again since I think a timeout after ~1hour is better than the CI job being cancelled after 6 hours.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1635470616
https://github.com/pydata/xarray/pull/7657#issuecomment-1479671510,https://api.github.com/repos/pydata/xarray/issues/7657,1479671510,IC_kwDOAMm_X85YMf7W,14808389,2023-03-22T14:29:20Z,2023-03-22T14:29:20Z,MEMBER,"apparently python 3.11 on windows is also pretty slow, which makes the timeouts appear there as well. But in any case, here's the affected tests:
```
FAILED xarray/tests/test_backends.py::TestDask::test_dask_roundtrip - Failed: Timeout >90.0s
FAILED xarray/tests/test_backends.py::TestDask::test_deterministic_names - Failed: Timeout >90.0s
FAILED xarray/tests/test_backends.py::TestDask::test_dataarray_compute - Failed: Timeout >90.0s
FAILED xarray/tests/test_backends.py::TestDask::test_load_dataset - Failed: Timeout >90.0s
FAILED xarray/tests/test_backends.py::TestDask::test_load_dataarray - Failed: Timeout >90.0s
FAILED xarray/tests/test_backends.py::TestDask::test_inline_array - Failed: Timeout >90.0s
FAILED xarray/tests/test_backends.py::TestPydap::test_cmp_local_file - Failed: Timeout >90.0s
FAILED xarray/tests/test_backends.py::TestPydap::test_compatible_to_netcdf - Failed: Timeout >90.0s
FAILED xarray/tests/test_backends.py::TestPydap::test_dask - Failed: Timeout >90.0s
```
which are the exact same tests that also fail for >300s, so I'm guessing those are the ones that stall.
Does anyone know why those take so long only on macos (and, partially, windows)? Does that have to do with the runner hardware?","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1635470616