CDC huge transactions waiting for commit (until target commit)

[desmondchew]

We have a table that is consistently showing high number of transactions (until target commit) under CDC. Is this an I/O issue at the target MySQL DB?

I have attached a screenshot to show the issue.

Thank you.

[john_wang]

Hello Desmond,

Maybe it's I/O issue in the target side eg it cannot swallow too many rows in time fashion, or there are other conditions/errors that lead the Offload transaction to Disk . You may tune the parameters, or enable TARGET_APPLY to Verbose, PERFORMANCE to Trace then check the task log file to see if any clue.

Hope this helps.

Regards,

John.

[desmondchew]

Hi John,

Is there any parameters we could tune to speed up the Offload transaction to Disk in target?

Thank you.

Desmond

[john_wang]

Hello @desmondchew ,

Please check Transaction offload tuning in Replicate User Guide. Hope it helps.

Regards,

John.