Reserve apartment contexts before push_back to reduce reallocations - #666
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zengelbrecht61-lgtm wants to merge 1 commit into
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Reserve apartment contexts before push_back to reduce reallocations#666zengelbrecht61-lgtm wants to merge 1 commit into
zengelbrecht61-lgtm wants to merge 1 commit into
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…eserve() call based on the apartment storage size before collecting apartment contexts to avoid repeated reallocations while holding the lock.\n\nCo-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
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Chris Guzak (@ChrisGuzak) IIRC you wrote most of this code, so you'd be able to better comment on this than me. From the code, not all contexts are pushed into the vector, so this is likely going to over-allocate. That's probably fine - vector is likely going to over-allocate when it doubles its size the final time - however your description is missing the very important why? What problem are you trying to solve? |
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Summary
Pre-size the apartment context collection before pushing entries into the vector so it avoids repeated reallocation while the apartment lock is held.
Why
The apartment migration code collects context pointers and then appends them back into a vector each time it enumerates the apartment set. The vector grew one element at a time, which caused repeated reallocation and copy churn under the lock.
What changed
Validation