feat: Add LFU Eviction Policy with LRU tie-breaking#90
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| """ | ||
| Unit tests for LFUEvictionPolicy. | ||
| Run with: pytest tests/test_lfu_eviction_policy.py -v | ||
| """ |
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Please move the test to the respective unit test location in tests/unit/EvictionPolicyStrategy
luis-gasparschroeder
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Jun 18, 2026
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| class LFUEvictionPolicy(EvictionPolicy): | ||
| """ | ||
| Least Frequently Used (LFU) eviction policy with LRU tie-breaking. | ||
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| Tracks access_count per entry. Evicts lowest-frequency entries first. | ||
| Ties broken by last_accessed (oldest evicted first). | ||
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| Args: | ||
| max_size (int): Maximum number of entries before eviction triggers. | ||
| watermark (float): Fraction of max_size that triggers eviction. | ||
| eviction_percentage (float): Fraction of max_size to evict per cycle. | ||
| """ |
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We already have an LRU policy in vcache/vcache_core/cache/eviction_policy/strategies/lru.py. Please extend that instead of implementing a new one.
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Summary
This PR adds LFUEvictionPolicy to vCache.
Motivation
Existing policies are recency-based. LFU retains high-value entries regardless of recency, improving hit rates on skewed workloads.
Changes
Tests
pytest tests/test_lfu_eviction_policy.py -v # 16 passed