aspect: keep lat/lon chunked in dask+cupy geodesic path (#2688)#2707
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brendancol wants to merge 4 commits into
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aspect: keep lat/lon chunked in dask+cupy geodesic path (#2688)#2707brendancol wants to merge 4 commits into
brendancol wants to merge 4 commits into
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The geodesic dask+cupy backend converted the full lat/lon broadcast views to cupy with cupy.asarray up front, densifying the whole (H, W) grid onto a single GPU at graph-construction time. Peak GPU memory scaled with the full array instead of the chunk size, so large rasters would OOM on the GPU. Build the lat/lon dask arrays from the numpy broadcast views and convert each block to cupy lazily via map_blocks, so only one chunk lands on the GPU at a time. The dask+numpy path already did the right thing. Add a graph-construction test (no compute) asserting the full lat/lon grids are not materialized on the GPU when the graph is built.
…e-aspect-2026-05-29
…e-aspect-2026-05-29
Add a one-line note that the module-level cupy reference in _to_cupy_f64 is always the real cupy module, since the helper is only reached from the dask+cupy backend. Addresses a review nit on PR #2707.
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Closes #2688
The geodesic dask+cupy
aspect()path converted the full lat/lon broadcast views to cupy withcupy.asarray()at graph-construction time, densifying the whole (H, W) grid onto a single GPU before chunking. Peak GPU memory scaled with the full array, so large rasters would OOM on the GPU.map_blocks, so only one chunk lands on the GPU at a time.Backend coverage: only the dask+cupy geodesic path changed. numpy, cupy, dask+numpy, and all planar paths are untouched.
Test plan:
xrspatial/tests/test_geodesic_aspect.pypasses (including dask+cupy correctness vs numpy)xrspatial/tests/test_aspect.pypasses