MySQL Bugs: #107493: Update longblob column hangs with mysqlrouter 8.0.29

Bug #107493	Update longblob column hangs with mysqlrouter 8.0.29
Submitted:	6 Jun 2022 8:26	Modified:	16 Aug 2022 10:47
Reporter:	Liang Cheng	Email Updates:
Status:	Duplicate	Impact on me:	None
Category:	MySQL Router	Severity:	S1 (Critical)
Version:	8.0.29	OS:	CentOS (7.5)
Assigned to:		CPU Architecture:	Any
Tags:	mysqlrouter 8.0.29 hang

Description:
The MySQL cluster includes following components
1. 3 MySQL server(8.0.29) as the group replication members, one primary and two slaves
2. mysqlrouter 8.0.29
3. mysqlshell 8.0.29

The test code is attached below.
NOTE: 
1. If change the port from 6446 (mysqlrouter) to 3308 (MySQL server), no issue
2. If install mysqlrouter/mysqlshell 8.0.28 rather 8.0.29, no issue
3. make sure the file size of is not small. The file I used is about 27M

How to repeat:
Table schema
CREATE TABLE bundle (
id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR (255) NOT NULL,
image LONGBLOB NOT NULL
);

Test code
Connection conn = DriverManager.getConnection("JDBC:MYSQL://ip:6446/test?useSSL=false", "root", "password");
    	PreparedStatement pStmt = conn.prepareStatement("update bundle set image = ? where id =2");
    	String filePath = args[0];
    	File file = new File(filePath);
    	FileInputStream fis = new FileInputStream(file);
    	pStmt.setObject(1, fis);
    	pStmt.executeUpdate();
    	fis.close();
	conn.close();

//The file size is about 27M.
//

Hi,

Can you try to disable server side prepared statements by adding to your DSN

useServerPrepStmts=false

and retest this

thanks

Adding useServerPrepStmts=false doesn't work.

Hi,
what do you mean by "don't work"
 - you cannot run the test
 - you cannot reproduce the problem
 - test behaves exactly the same

thanks

I meant to the say is same, when updating, the thread hang there and could not return

Hi,

Thanks, this is a different bug from what I assumed originally. Mysqlrouter is failing with big packet.

Posted by developer:
 
Thanks for the report.

The described problems is the same as Bug#34426322.

An existing bug report already describes this very problem as Bug#107982

Even if you feel that your issue is somewhat different, the resolution is likely
to be the same. Because of this, we hope you add your comments to the original bug instead.

Thank you for your interest in MySQL.