Quadratic definition time in xarray.DataArray.to_zarr(compute=False)#12299
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crusaderky merged 2 commits intodask:mainfrom Feb 19, 2026
Merged
Quadratic definition time in xarray.DataArray.to_zarr(compute=False)#12299crusaderky merged 2 commits intodask:mainfrom
crusaderky merged 2 commits intodask:mainfrom
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Unit Test ResultsSee test report for an extended history of previous test failures. This is useful for diagnosing flaky tests. 21 files ±0 21 suites ±0 5h 4m 6s ⏱️ - 3m 58s Results for commit 949cead. ± Comparison against base commit 6ac1553. |
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Thank you! We've seen many reports of it and have recommend people just use chunksize=-1, most of the time no one actually computes the returned Delayed anyway, it is simply used for writing a schema. |
dcherian
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Feb 19, 2026
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Closes #12298
Reduce the time it takes for
xarray.DataArray.to_zarr(..., compute=False)to return a delayed object from O(n^2) to O(n), where n is the total number of tasks in the graph.In my production environment, this reduces the time it takes to store the metadata of an array backed by a ~70k tasks graph from 3 minutes to 2 seconds.
Read #12298 for full explanation and analysis.
No unit test since, AFAIK, there are no microbenchmarks available?