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@bnbajwa bnbajwa commented Nov 6, 2025

memcpy can be faster. std::copy results in call to memmove if compiler can't be certain that the memory regions do not overlap.

SDB-10043

memcpy can be faster

SDB-10043
@bnbajwa bnbajwa requested a review from a team as a code owner November 6, 2025 14:03
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Summary of Changes

Hello @bnbajwa, I'm Gemini Code Assist1! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a performance optimization by switching from std::copy to std::memcpy for copying raw character data within the OStreamBase utility. This change is aimed at leveraging the potentially faster, byte-level memory transfer capabilities of memcpy for Plain Old Data (POD) types, thereby enhancing the efficiency of data handling operations.

Highlights

  • Performance Optimization: Replaced std::copy with std::memcpy in the put_data method of OStreamBase to potentially improve performance for raw data copying.
  • Header Inclusion: Added the <cstring> header to OStreamBase.hpp to provide the declaration for std::memcpy.
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Code Review

This pull request aims to improve performance by replacing std::copy with std::memcpy in OStreamBase::put_data. While memcpy can be faster, it introduces the risk of undefined behavior if the source and destination memory regions overlap. My feedback suggests using std::memmove instead, which is safe for overlapping regions and generally has comparable performance. This ensures correctness against potential edge cases without sacrificing the intended performance gain.

@bnbajwa bnbajwa enabled auto-merge (rebase) November 6, 2025 14:08
@bnbajwa bnbajwa merged commit 7d94304 into reactivemarkets:master Nov 6, 2025
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@bnbajwa bnbajwa deleted the logp branch November 6, 2025 14:35
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