[tidb-x] after pd switching leader, the heartbeat between tikv and pd was abnormal and could not be recovered

[Lily2025]

Bug Report

What did you do?

1、run sysbench
2、add index for one table
3、simulated pd io delay 5s which trigger pd restart

What did you expect to see?

after pd recover，tikv and pd can communicate normally

What did you see instead?

after switching leader, the heartbeat between tikv and pd was abnormal and could not be recovered

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

./pd-server -V
Release Version: v8.5.4-nextgen.202510.6-1-g17478bb
Edition: Enterprise
Kernel Type: Next Generation
Git Commit Hash: 17478bb
Git Branch: HEAD
UTC Build Time: 2026-01-22 03:25:59
2026-02-08T08:18:51.144+0800

[Lily2025]

/severity critical

[Lily2025]

/assign bufferflies