Making Allocators Work, Part I

on YouTube ↗49m

" summary

Explains the concrete C++11/14 changes: introduces allocator_traits and a polymorphic allocator runtime model, shows a built example — a monotonic memory resource that allocates from a stack buffer and falls back to heap — used to back three vectors of 100 doubles. Demonstrates it works and makes prior allocator experiments practical, but reports measurable caveats: occasional slower fallback allocations, no per-allocation deallocation, stack exhaustion and alignment pitfalls, and allocator propagation defaults that do not move state.

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" chapters (13)

1. 0:00Intro
2. 1:15Topics to cover
3. 2:36What is an allocator?
4. 3:19Goal: per-object allocation
5. 4:52Motivating Examples
6. 6:53Buffered Sequential Allocator: design
7. 9:50Buffered Sequential Allocator: benefits
8. 10:26Buffered Sequential Allocator: risks
9. 22:00Example of Using Allocators Library Fundamentals Polymorphic Allocators
10. 27:02Vocabulary Types
11. 30:33Weasel Words
12. 38:54Allocator Propagation
13. 41:02Allocator Traits

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