MySQL Bugs: #106907: Backup::get_total_memory returns incorrect result

Bug #106907	Backup::get_total_memory returns incorrect result
Submitted:	4 Apr 16:15	Modified:	5 Apr 6:04
Reporter:	Mikael Ronström	Email Updates:
Status:	Verified	Impact on me:	None
Category:	MySQL Cluster: Cluster (NDB) storage engine	Severity:	S3 (Non-critical)
Version:	8.0.23	OS:	Any
Assigned to:		CPU Architecture:	Any

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Description:
get_total_memory is used to calculate proposed disk write speed for
checkpoints. It assumes that the LDM threads has even usage of
DataMemory which is not necessarily true.

How to repeat:
Run write benchmark and see LCP times increase with ClassicFragmentation=0.

Suggested fix:
Use variable m_pages_allocated in DBTUP to calculate total DataMemory
used by the LDM thread multiplied by the page size.

Hello Mikael,

Thank you for the report and feedback.

Sincerely,
Umesh