merge operator blocks the balance leader operations

[rleungx]

Bug Report

What did you do?

Run a cluster, kill one TiKV, and restart it.

What did you expect to see?

The leader should be balanced quickly.

What did you see instead?

The merge operator spends 10 mins to become timeout. In this period, the balance leader cannot run due to the leader limit. Besides, one merge operator will occupy two leader limits if it contains a transfer leader step.

What version of PD are you using (pd-server -V)?

v5.0.2

[Lily2025]

/severity Moderate

[nolouch]

/assign

[rleungx]

not only balance leader, may also block evict leader

[nolouch]

/assign @bufferflies

[ti-chi-bot]

@nolouch: GitHub didn't allow me to assign the following users: bufferflies.

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In response to this:

/assign @bufferflies

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