feat: Allow logging path to be warmed

[bnbajwa]

SDB-10043

[gemini-code-assist]

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 significant enhancement to the logging infrastructure by enabling a "warming" mode. This mode allows the logging code path to be exercised without incurring the overhead of actual log message processing and I/O operations. By introducing a warming_fake flag, various logger implementations can conditionally skip expensive operations, making it ideal for performance benchmarking, system initialization, or stress testing where the logging mechanism needs to be active but its side effects temporarily suppressed.

Highlights

• Logging Warming Mode: Introduced a new "warming" mode for the logging system, allowing log calls to execute without performing actual I/O operations.
• warming_fake Parameter: Added a bool warming_fake parameter to the do_write_log methods across various logger implementations to control the fake logging behavior.
• Per-Thread Control: Implemented set_log_warming_mode and log_warming_mode_enabled functions, utilizing a thread_local variable, to manage the warming mode on a per-thread basis.
• AsyncLogger Enhancements: The AsyncLogger now handles "fake" log entries by pushing nullptr to its internal queue, with rate limiting to prevent flooding, and correctly accounts for these fake entries during processing.

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[gemini-code-assist]

Code Review

This pull request introduces a 'warming' mode for the logging system, which is a good feature for performance-sensitive applications to avoid cold-start latency. The implementation is well-thought-out, especially the throttling mechanism for fake log messages in the AsyncLogger to prevent queue flooding. The changes are consistent across different logger implementations. I've found a couple of minor issues related to code consistency and style that I've detailed in my comments.

[Copilot]

Pull Request Overview

This PR introduces a log warming mode feature that allows the logging code paths to be exercised without producing actual log output. This is useful for performance optimization by "warming up" the logging infrastructure (e.g., pre-allocating memory, exercising code paths) before critical operations.

Key Changes

• Added per-thread warming mode control via set_log_warming_mode() and log_warming_mode_enabled() functions
• Modified all Logger implementations to accept a warming_fake parameter that suppresses actual log output when enabled
• Enhanced AsyncLogger to push placeholder entries to the queue during warming mode with rate limiting to maintain queue responsiveness

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
toolbox/sys/Logger.hpp	Added warming mode API functions, updated Logger interface signatures, and added AsyncLogger member variables for tracking fake queue entries
toolbox/sys/Logger.cpp	Implemented warming mode functions, updated all logger implementations to handle warming mode, and added AsyncLogger logic to push/track fake entries with rate limiting
toolbox/sys/Log.ut.cpp	Updated TestLogger to handle the new warming_fake parameter
bench/Log.bm.cpp	Updated FileLogger benchmark to handle the new warming_fake parameter

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[Copilot]

Pull Request Overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

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