add index for small partition table on v8.1.0 is slower than it on v7.5.1 #54230
Description
Bug Report
Please answer these questions before submitting your issue. Thanks!
1. Minimal reproduce step (Required)
drop table if exists tt1, tt2;
set global tidb_partition_prune_mode='dynamic';
set session tidb_partition_prune_mode='dynamic';
CREATE TABLE tt1 (
id INT NOT NULL,
listid INT,
name varchar(10),
primary key (listid) clustered
)
PARTITION BY LIST (listid) (
PARTITION p1 VALUES IN (1),
PARTITION p2 VALUES IN (2),
PARTITION p3 VALUES IN (3),
PARTITION p4 VALUES IN (4)
);
CREATE TABLE tt2 (
id INT NOT NULL,
listid INT
);
create index idx_listid on tt1(id,listid);
create index idx_listid on tt2(listid);
2. What did you expect to see? (Required)
3. What did you see instead (Required)
on v7.5.1 cluster
mysql> create index idx_listid on tt1(id,listid);
Query OK, 0 rows affected (0.58 sec)
mysql> create index idx_listid on tt2(listid);
Query OK, 0 rows affected (0.51 sec)
on v8.1.0 and nightly cluster
mysql> create index idx_listid on tt1(id,listid);
Query OK, 0 rows affected (1.99 sec)
mysql> create index idx_listid on tt2(listid);
Query OK, 0 rows affected (1.35 sec)
tidb_enable_dist_task is off in v7.5.1, and on in 8.1.0
4. What is your TiDB version? (Required)
v8.1.0 and master