infochema, server: export region_id in hot_region table

[lysu]

What problem does this PR solve?

• add REGION_ID to information_schema.TIDB_HOT_REGIONS so we can join other table to find sth like "hot store name", "hot key ranges".
• add infinity timeout to fetch hot region info from pd api(this api is slow when there are too many regions, current timeout value is not suitable)
• fix mistake for column order in TIKV_REGION_PEERS

What is changed and how it works?

just as above described

Check List

Tests

• Manual test (add detailed scripts or steps below)

run sysbench prepare will saw this:

mysql> select * from TIDB_HOT_REGIONs;
+----------+----------+---------+------------+------------+-----------+-------+----------------+--------------+------------+
| TABLE_ID | INDEX_ID | DB_NAME | TABLE_NAME | INDEX_NAME | REGION_ID | TYPE  | MAX_HOT_DEGREE | REGION_COUNT | FLOW_BYTES |
+----------+----------+---------+------------+------------+-----------+-------+----------------+--------------+------------+
|       48 |     NULL | sbtest  | sbtest27   | NULL       |         5 | write |              4 |            0 |     569174 |
|       59 |     NULL | sbtest  | sbtest26   | NULL       |        92 | write |              4 |            0 |     569174 |
|       84 |     NULL | sbtest  | sbtest9    | NULL       |       140 | write |              4 |            0 |     569174 |
+----------+----------+---------+------------+------------+-----------+-------+----------------+--------------+------------+
3 rows in set (0.02 sec)


{
 "read": [],
 "write": [
  {
   "region_id": 160,
   "region_metric": {
    "flow_bytes": 624177,
    "max_hot_degree": 3,
    "region_count": 0
   },
   "db_name": "sbtest",
   "table_name": "sbtest28",
   "table_id": 46,
   "index_name": "",
   "index_id": 0
  },
  {
   "region_id": 156,
   "region_metric": {
    "flow_bytes": 624177,
    "max_hot_degree": 3,
    "region_count": 0
   },
   "db_name": "sbtest",
   "table_name": "sbtest32",
   "table_id": 54,
   "index_name": "",
   "index_id": 0
  },
  {
   "region_id": 136,
   "region_metric": {
    "flow_bytes": 624177,
    "max_hot_degree": 3,
    "region_count": 0
   },
   "db_name": "sbtest",
   "table_name": "sbtest18",
   "table_id": 62,
   "index_name": "",
   "index_id": 0
  },
....

Code changes

• N/A

Side effects

• N/A

Related changes

• Need to cherry-pick to the release 3.0

---

This change is 

[lysu]

/run-all-tests

[codecov]

Codecov Report

Merging #10982 into master will not change coverage.
The diff coverage is n/a.

@@             Coverage Diff             @@
##             master     #10982   +/-   ##
===========================================
  Coverage   81.2626%   81.2626%           
===========================================
  Files           423        423           
  Lines         90781      90781           
===========================================
  Hits          73771      73771           
  Misses        11705      11705           
  Partials       5305       5305

[jackysp]

LGTM

[imtbkcat]

/run-all-tests

[imtbkcat]

/run-all-tests

[imtbkcat]

/run-unit-test

[imtbkcat]

@lysu please fix test

[lysu]

/run-all-tests

[lysu]

/run-unit-test

[lysu]

/run-unit-test

[lysu]

/run-all-tests

[lysu]

@imtbkcat PTAL again thx~

[lysu]

/run-all-tests

[lysu]

/run-unit-test

[lysu]

/run-all-tests

[lysu]

/rebuild

[imtbkcat]

LGTM