Bug #103291 MySQL 2GB RAM innodb_dedicated_server = 1 causes only 1 log file to be created

• Submitted: 12 Apr 2021 17:52
• Modified: 14 Apr 2021 12:53
• Reporter: Adam Cable (OCA)
• Status: Verified
• Category: MySQL Server: InnoDB storage engine
• Severity: S3 (Non-critical)
• Version: 8.0
• OS: Any
• CPU Architecture: Any

[12 Apr 2021 17:52] Adam Cable

Description:
If the VM has 2GB of RAM, and you use the innodb_dedicated_server = 1 declaration, then the server fails to boot as it only creates a single log file.
This is because the current code doesn't cater for when the automatic buffer pool size is set to 1GB.
The amended code ensures that at least 2 log files are created.

How to repeat:
Create a VM with 2GB of RAM and set innodb_dedicated_server = 1

Suggested fix:
You can fix it in the config by setting innodb_log_files_in_group = 2, but this situation should be handled automatic by the Dedicated Server logic.

Pull request https://github.com/mysql/mysql-server/pull/334 fixes this in code.

[12 Apr 2021 17:53] Adam Cable

And for completeness, error is logged as:
[MY-012961] [InnoDB] Only one log file found

[13 Apr 2021 13:04] MySQL Verification Team

Hi Mr. Cable,

Thank you for your bug report.

However, we need more data in order to proceed.

What exactly is the size of the innodb buffer pool and how many pools are there ????

If you read section 15.8.12  in our Manual, that value should be 2, unless it is some boundary problem.

[13 Apr 2021 13:16] MySQL Verification Team

Hi,

After further evaluation, we decided to verify this bug. Simply, with that setting, it is our responsibility not to set variables to incorrect values.

However, your response is still required.

Verified as reported.

[13 Apr 2021 13:37] Adam Cable

Hi,

We simply did the following:

 - Create a VM with 2GB Ram
 - Installed MySQL server
 - Set "
[mysqld]
innodb_dedicated_server = 1
" as the my.cnf file

No other settings were set; this one option should auto-configure everything we need.

Happy to provide any other information you require.

Thanks,
Adam

[14 Apr 2021 12:52] MySQL Verification Team

Hi Mr. Cable,

Can you please upload, in this report, the values of all the configuration variables for that instance.

[14 Apr 2021 12:53] Adam Cable

Hi,

As mentioned above - we only had "innodb_dedicated_server = 1" set in our my.cnf file.

Thanks.