the 'txn-entry-size-limit' config is not effective in DM

[zwathz]

What did you do?

https://asktug.com/t/topic/694876

TiDB config:

+------+---------------------+--------------------------------------+-----------+
| Type | Instance            | Name                                 | Value     |
+------+---------------------+--------------------------------------+-----------+
| tidb | xxxxx:4000 | performance.txn-entry-size-limit     | 125829120 |
| tikv | xxxxx:20161 | raftstore.raft-entry-max-size        | 128MiB    |
+------+---------------------+--------------------------------------+-----------+

DM error:

"errors": [
      {
          "ErrCode": 50000,
          "ErrClass": "not-set",
          "ErrScope": "not-set",
          "ErrLevel": "high",
          "Message": "[kv:8025]entry too large, the max entry size is 6291456, the size of data is 7890542",
          "RawCause": "",
          "Workaround": ""
      }
],

What did you expect to see?

DM task work normally.

What did you see instead?

DM task get an error.

Versions of the cluster

DM version (run dmctl -V or dm-worker -V or dm-master -V):

tiup is checking updates for component dmctl ...
Starting component `dmctl`: /home/admin/.tiup/components/dmctl/v6.1.0/dmctl/dmctl -V
Release Version: v6.1.0
Git Commit Hash: 9f5e3cea2fae0a3dce6cc5ca79e3bcd654b8aa99
Git Branch: heads/refs/tags/v6.1.0
UTC Build Time: 2022-06-07 11:55:24
Go Version: go version go1.18.2 linux/amd64

TiDB Version

MySQL [(none)]> SELECT tidb_version()\G
*************************** 1. row ***************************
tidb_version(): Release Version: v6.1.0
Edition: Community
Git Commit Hash: https://github.com/pingcap/tidb/commit/1a89decdb192cbdce6a7b0020d71128bc964d30f
Git Branch: heads/refs/tags/v6.1.0
UTC Build Time: 2022-06-05 05:15:11
GoVersion: go1.18.2
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false
1 row in set (0.00 sec)

current status of DM cluster (execute query-status <task-name> in dmctl)

(paste current status of DM cluster here)

[lance6716]

This problem is caused by DM's embedded TiDB. Since #4477, we use BatchCreateTableWithInfo to load table structure. If the table number is too large, the batch will exceed KV entry size.

To walkaround, you can let a task contain less tables to synchronize

[lance6716]

/assgin @ForwardStar

[lance6716]

/assign @ForwardStar