Parallel redo is started for database

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1

Hello

I have a sql 2017 Standard

Several times this warning apears in logs:

SPID52 Parallel redo is started for database xxxx with worker pool size (6)
and immediately arises the other one
SPID52 Parallel redo is shuting down for database xxxx with worker pool size (6)

Those messages arise when backups are iniciated (maintenance plan)

Can I have some help?

Thanks

2

Is this all on one SQL Server instance? When you say "other one" do you mean a replica of some kind? Availability group?

If you are backing up a transaction log, I could see that parallel redo is paused while the backup is running, as concurrent writes could interfere with it. I don't have documentation on that, but it makes sense.

In any case, I don't think it's anything to worry about.

3

Hi Robert

Is this all on one SQL Server instance?
.... yes. I do not use replicas. The databases aren't participating in an Availability Group.

When you say "other one" do you mean a replica of some kind?
... What I pretend to explain is that the two warnings (SPID52 Parallel redo is started for database xxxx with worker pool size (6) and SPID52 Parallel redo is shuting down for database xxxx with worker pool size (6)) occurs almost simultaneously.

Is there a way to stop these messages?

Thanks in advanced

4

You can set trace flag 3459 to disable parallel redo:

Suggest you read the accompanying blog before setting it:

There's some commentary here as well, that it's a perfectly normal message:

Disabling it could negatively impact your server performance.

1 Like
5

Thank you Robert