dashboard queries cluster_statements_summary_history causes tidb-server OOM

[XuHuaiyu]

Bug Report

Please answer these questions before submitting your issue. Thanks!

What did you do?
As the title says.

We see some sql like this :

 SELECT FLOOR(UNIX_TIMESTAMP(MIN(summary_begin_time))) AS agg_begin_time, FLOOR(UNIX_TIMESTAMP(MAX(summary_end_time))) AS agg_end_time, ANY_VALUE(digest_text) AS agg_digest_text, ANY_VALUE(digest) AS agg_digest, SUM(exec_count) AS agg_exec_count, SUM(sum_latency) AS agg_sum_latency, MAX(max_latency) AS agg_max_latency, MIN(min_latency) AS agg_min_latency, CAST(SUM(exec_count * avg_latency) / SUM(exec_count) AS SIGNED) AS agg_avg_latency, ANY_VALUE(schema_name) AS agg_schema_name, COUNT(DISTINCT plan_digest) AS agg_plan_count FROM `INFORMATION_SCHEMA`.`CLUSTER_STATEMENTS_SUMMARY_HISTORY` WHERE (summary_begin_time <= FROM_UNIXTIME(?) AND summary_end_time >= FROM_UNIXTIME(?)) AND (LOWER(digest_text) REGEXP ?
                                 OR LOWER(digest) REGEXP ?
                                 OR LOWER(schema_name) REGEXP ?
                                 OR LOWER(table_names) REGEXP ?
                                 OR LOWER(plan) REGEXP ?) GROUP BY schema_name, digest ORDER BY agg_sum_latency DESC

What did you expect to see?

TiDB does not OOM

What did you see instead?

TiDB OOM

What version of TiDB Dashboard are you using (./tidb-dashboard --version)?

v6.1