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ClickHouse/tests/queries/0_stateless/01017_uniqCombined_memory_usage.reference

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Do not use more then 98K of memory for uniqCombined* uniqCombined() uses hashtable for medium cardinality, and since HashTable resize by the power of 2 (well actually HashTableGrower grows double by the power of 2, hence HashTableGrower::increaseSize() should be overwritten to change this), with 1<<13 (default for uniqCombined) and UInt64 HashValueType, the HashTable will takes: getBufferSizeInBytes() == 131072 While it should be not greater then sizeof(HLL) ~= 98K, so reduce the maximum cardinality for hashtable to 1<<12 with UInt64 HashValueType and to 1<13 with UInt32, overwrite HashTableGrower::increaseSize() and cover this using max_memory_usage. Refs: https://github.com/ClickHouse/ClickHouse/pull/7221#issuecomment-539672742 v2: cover uniqCombined() with non-default K
2019-10-08 20:26:31 +00:00
UInt32
819200
UInt64
409600
K=16
UInt32
409600
UInt64
204800
K=18
UInt32
1638400
UInt64
819200
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