Memory is not returned when ENGINE=Memory table is dropped #9248
Description
Describe the bug or unexpected behaviour
Memory is not returned when a table with ENGINE=Memory is dropped!
How to reproduce
- ClickHouse server version 20.+
- Running the following snippet will waste around 4Gb of RAM
CREATE DATABASE IF NOT EXISTS test_memory_leak
CREATE TABLE test_memory_leak.table1 (x1 UInt8) ENGINE = Memory
INSERT INTO test_memory_leak.table1 SELECT materialize(0) AS x1 FROM numbers(4000000000)
SELECT 1
TRUNCATE TABLE test_memory_leak.table1
DROP TABLE test_memory_leak.table1
DROP DATABASE test_memory_leak
- Running it in a loop eventually gets ClickHouse server OOMed