fix(cache): add exponential backoff for failed cache flush attempts#588
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Implement rate limiting for cache recycler flush operations to prevent performance degradation when cache limits are reached and memory cannot be freed. When flush attempts fail to release sufficient memory (less than 10% of target flush size), the system now applies exponential backoff starting at 1 microsecond and doubling up to a maximum of 1 second between retry attempts. This prevents the cache recycler from hammering the system with continuous flush attempts that cannot succeed. Key changes: - Add m_next_flush_time timestamp to track next allowed flush moment - Add m_current_flush_delay for exponential backoff tracking - Flush attempts only execute if current time >= m_next_flush_time - Success threshold: flushed size > 10% of target flush size - On success: reset delay to zero for immediate future flushes - On failure: double delay (1μs → 2μs → 4μs → ... → 1s max) Fixes #539
wskozlowski
reviewed
Dec 6, 2025
| updateSize(lock, m_capacity - flush_size); | ||
| flushed = true; | ||
| flush_result = m_current_size[priority] <= (m_capacity - flush_size); | ||
| auto now = std::chrono::high_resolution_clock::now(); |
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can we move this to a separate function ? this one is getting big and overly complex
…thod Extracted cache eviction and backoff logic from CacheRecycler::update() into a new private _flush() helper method to improve code maintainability and reduce method complexity.
wskozlowski
approved these changes
Dec 7, 2025
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Implement rate limiting for cache recycler flush operations to prevent performance degradation when cache limits are reached and memory cannot be freed.
When flush attempts fail to release sufficient memory (less than 10% of target flush size), the system now applies exponential backoff starting at 1 microsecond and doubling up to a maximum of 1 second between retry attempts. This prevents the cache recycler from hammering the system with continuous flush attempts that cannot succeed.
Key changes:
Fixes #539