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Storage page cache uses plain LRU Cache, occasional batch operations can cause "cache pollution" in plain LRU Cache. This will cause hotspot data to be squeezed out of the cache by non-hotspot data, reduce cache hit rate.
In extreme cases, if the number of pages inserted each time is greater than the cache capacity, the cache hit rate will be 0.
Introducing LRU-K Cache avoids "cache pollution" in most cases.
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What problem does this PR solve?
Storage page cache uses plain LRU Cache, occasional batch operations can cause "cache pollution" in plain LRU Cache. This will cause hotspot data to be squeezed out of the cache by non-hotspot data, reduce cache hit rate.
In extreme cases, if the number of pages inserted each time is greater than the cache capacity, the cache hit rate will be 0.
Introducing LRU-K Cache avoids "cache pollution" in most cases.
Last submitted #28794
Similar PR: #23546
Performance test on branch-2.1:
1-FE, 3-BE (32 Core, 128GB Memory) Doris cluster
ssb_sf_1000
all query cost: 18.85s -> 14.44s, 23% improvementssb_flat_1000
all query cost: 12.21s -> 8.54s, 30% improvement, cache hit rate 1% -> 40%Check List (For Author)
Test
Behavior changed:
Does this need documentation?
Check List (For Reviewer who merge this PR)