Optimize memory allocation in stops-for-route polyline generation#299
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aaronbrethorst merged 1 commit intoOneBusAway:mainfrom Feb 6, 2026
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Pre-allocate the coords slice in generatePolylines to the known capacity of shapes. This eliminates repeated memory resizing and copying during iteration, reducing garbage collection pressure for routes with many shape points.
aaronbrethorst
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Feb 6, 2026
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Hey Aditya, thanks for this allocation optimization to generatePolylines. The change is spot-on — since every element in shapes produces exactly one coordinate pair, pre-allocating with len(shapes) is the ideal capacity and completely eliminates intermediate slice growth.
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Description:
This PR optimizes the
generatePolylinesfunction ininternal/restapi/stops_for_route_handler.goby pre-allocating the coordinate slice.Changes:
coordsslice tolen(shapes)to prevent repeated memory re-allocations during iteration.Note: This applies the same optimization pattern recently added to the shapes handler.
Closes #298