Direct IO does not work with PREWHERE when there are multiple threads

[alexey-milovidov]

CREATE TABLE bug (UserID UInt64, Date Date) ENGINE = MergeTree ORDER BY Date;
INSERT INTO bug SELECT rand64(), '2020-06-07' FROM numbers(153656686);

clickhouse-benchmark --max_threads 16 --min_bytes_to_use_direct_io 1 <<< "SELECT UserID FROM geo_bug_2 PREWHERE NOT ignore(Date)"

Data compressed with different methods, given method byte 0x40, previous method byte 0x82: (while reading column UserID): (while reading from part ./data/default/geo_bug_2/all_1_142_3/ from mark 1720 with max_rows_to_read = 65536): While executing MergeTreeThread.

[alexey-milovidov]

Affected versions:

master
20.4
20.3
20.1.12
19.14 (difficult to reproduce, only after 52 queries)
19.1.16 (with another error message: "Can't adjust last granule because it has 8192rows, but try to subtract 49152 rows.")
18.16 (the same error message as 19.1)