Deleted initialNumReaders paramter.

[AdalbertMemSQL]

Deleted initialNumReaders paramter.
Pre-split restrictions to the maximum number of readers.
See the discussion in the design doc for more details.

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[AdalbertMemSQL]

addresses #22617

[AdalbertMemSQL]

R: @lukecwik

[AdalbertMemSQL]

R: @Abacn

[github-actions]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control

[AdalbertMemSQL]

R: @johnjcasey

[Abacn]

Run Java SingleStoreIO Performance Test

[Abacn]

Thanks. Followed the discussion but in case I missed something, could you please summarize the pros/cons of removing this parameter?

[AdalbertMemSQL]

Hi @Abacn

Sure.
Pros:

• it will make configuration easier as users will have fewer parameters
• the runner will fully control the parallelism and the user won't need to worry about it
  I don't see any cons.

@lukecwik Do you have something to add?

[Abacn]

Thanks, this looks good to me.

[Abacn]

okay, let us get this in before release cut to avoid a breaking change in released version