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Robert Schulze 2023-01-04 14:07:21 +00:00
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@ -130,7 +130,7 @@ private:
/// Implementation note: The query result implements a custom caching mechanism and doesn't make use of CacheBase, unlike many other
/// internal caches in ClickHouse. The main reason is that we don't need standard CacheBase (S)LRU eviction as the expiry times
/// associated with cache entries provide a "natural" eviction criterion. As a future TODO, we could make an expiry-based eviction
/// policy and use that with CacheBase.
/// policy and use that with CacheBase (e.g. see #23706)
/// TODO To speed up removal of stale entries, we could also add another container sorted on expiry times which maps keys to iterators
/// into the cache. To insert an entry, add it to the cache + add the iterator to the sorted container. To remove stale entries, do a
/// binary search on the sorted container and erase all left of the found key.