tidb panic when scale in pd from 6 to 3

[Lily2025]

Bug Report

What did you do?

1、scale out pd from 3 to 6
2、scale in pd from 6 to 3

What did you expect to see?

no painc

What did you see instead?

tidb panic

2024-01-23 12:39:28 log="2024-01-23T12:39:28.886543139+08:00 stderr F \t/go/pkg/mod/github.com/tikv/client-go/[email protected]/tikv/kv.go:243 +0x585"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886536764+08:00 stderr F created by github.com/tikv/client-go/v2/tikv.NewKVStore in goroutine 1"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886530142+08:00 stderr F \t/go/pkg/mod/github.com/tikv/client-go/[email protected]/tikv/kv.go:589 +0x1ef"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886523844+08:00 stderr F github.com/tikv/client-go/v2/tikv.(*KVStore).safeTSUpdater(0xc000e19ce0)"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886516936+08:00 stderr F \t/go/pkg/mod/github.com/tikv/client-go/[email protected]/tikv/kv.go:596 +0x4a"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886510506+08:00 stderr F github.com/tikv/client-go/v2/tikv.(*KVStore).updateSafeTS(0xc000e19ce0, {0x64174b8?, 0xc000708000?})"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886503905+08:00 stderr F \t/go/pkg/mod/github.com/tikv/client-go/[email protected]/tikv/kv.go:727 +0x92"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886497793+08:00 stderr F github.com/tikv/client-go/v2/tikv.(*KVStore).updateGlobalTxnScopeTSFromPD(0xc000e19ce0, {0x64174b8, 0xc000708000})"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886491476+08:00 stderr F \t/go/pkg/mod/github.com/tikv/client-go/[email protected]/tikv/kv.go:693 +0x46"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886481414+08:00 stderr F github.com/tikv/client-go/v2/tikv.(*KVStore).getMinResolvedTSByStoresIDs(0x0?, {0x64174b8?, 0xc000708000?}, {0x0?, 0x7ff0681065d0?, 0x7ff0b2276878?})"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886474765+08:00 stderr F \t/go/pkg/mod/github.com/tikv/pd/[email protected]/http/interface.go:749 +0x167"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886467608+08:00 stderr F github.com/tikv/pd/client/http.(*client).GetMinResolvedTSByStoresIDs(0x13?, {0x64174b8, 0xc000708000}, {0x0?, 0x13?, 0xc163ee985a977855?})"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886461023+08:00 stderr F \t/go/pkg/mod/github.com/tikv/pd/[email protected]/http/client.go:462 +0x92"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886454431+08:00 stderr F github.com/tikv/pd/client/http.(*client).request(0x0?, {0x64174b8?, 0xc000708000?}, 0x271ac85?, {0x0?, 0x0?, 0x0?})"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886446988+08:00 stderr F \t/go/pkg/mod/github.com/tikv/pd/[email protected]/http/client.go:184 +0x1ba"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886426927+08:00 stderr F github.com/tikv/pd/client/http.(*clientInner).requestWithRetry(0xc000faa400, {0x64174b8?, 0xc000708000}, 0xc003abb720, {0x0, 0x0, 0x0})"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886401748+08:00 stderr F \t/go/pkg/mod/github.com/tikv/pd/[email protected]/http/client.go:173 +0x9f8"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886393695+08:00 stderr F github.com/tikv/pd/client/http.(*clientInner).requestWithRetry.func1()"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886386189+08:00 stderr F goroutine 33 [running]:"
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886377561+08:00 stderr F "
2024-01-23 12:39:28 log="2024-01-23T12:39:28.886337968+08:00 stderr F panic: runtime error: index out of range [4] with length 3"

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

./pd-server -V
Release Version: v8.0.0-alpha
Edition: Community
Git Commit Hash: 6929c15
Git Branch: heads/refs/tags/v8.0.0-alpha
UTC Build Time: 2024-01-22 11:37:02
2024-01-23T11:50:19.632+0800

[Lily2025]

/type bug
/severity critical
/assign JmPotato

[JmPotato]

Fixed in master and only exists in v7.6.0.