feat: Use buffer pool for logging

[bnbajwa]

Eliminates dynamic allocations

The Log class now attempts to acquire a buffer from this pool before falling back to dynamic allocation. Various logger implementations (NullLogger, StdLogger, SysLogger, AsyncLogger) are updated to return the buffers to the pool after use.

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 implements a buffer pooling strategy for log messages to significantly reduce dynamic memory allocations, thereby improving logging performance and reducing memory fragmentation. By reusing pre-allocated message buffers, the system avoids the overhead of frequent new/delete calls during high-volume logging, contributing to a more efficient and stable application.

Highlights

• Introduced Log Buffer Pool: A boost::lockfree::stack is now used to manage a pool of LogMsgPtr buffers, pre-allocating 8 buffers at startup to reduce dynamic memory allocations.
• Eliminated Dynamic Allocations in Log Creation: The Log constructor now attempts to pop a buffer from the log_buf_pool. If the pool is empty, it falls back to LogStream::make_storage() for dynamic allocation.
• Returned Buffers to Pool: All logger implementations (NullLogger, StdLogger, SysLogger, AsyncLogger, and TestLogger) are updated to push the LogMsgPtr back into the log_buf_pool after processing, ensuring buffer reuse.
• Header Refactoring: Logger.hpp now declares the LogBufPool type and its accessor function, and header includes have been reordered for better organization.

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[gemini-code-assist]

Code Review

This pull request introduces a buffer pool for logging to eliminate dynamic memory allocations on the hot path. This is achieved by using a boost::lockfree::stack as a pool of log buffers. The Log class now attempts to acquire a buffer from this pool before falling back to dynamic allocation. Various logger implementations (NullLogger, StdLogger, SysLogger, AsyncLogger) are updated to return the buffers to the pool after use. The changes are correct and well-implemented. My review includes a couple of suggestions to replace magic numbers related to pool configuration with named constants to improve code readability and maintainability.

[Copilot]

Pull Request Overview

This PR implements a lock-free buffer pool for log message storage to reduce dynamic memory allocations during logging operations. The pool pre-allocates log buffers and reuses them across log operations.

• Introduces a global LogBufPool using boost::lockfree::stack with a capacity of 64 buffers
• Updates all logger implementations to return buffers to the pool after use
• Modifies the Log constructor to attempt to acquire a buffer from the pool before allocating new storage

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
toolbox/sys/Logger.hpp	Adds LogBufPool type alias and log_buf_pool() function declaration; reorganizes includes
toolbox/sys/Logger.cpp	Implements the buffer pool with initialization, adds buffer return logic to all logger implementations
toolbox/sys/Log.ut.cpp	Updates test logger to return buffers to the pool
toolbox/sys/Log.hpp	Modifies Log constructor to attempt to acquire buffers from the pool before allocating

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