From bf8d474070097f1e6d81ccc233dfc237ce0da5ae Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=B1=B1=E5=B2=9A?=
 <36239017+YuJuncen@users.noreply.github.com>
Date: Tue, 16 Jan 2024 17:55:45 +0800
Subject: [PATCH] restore_data: remove wait apply phase (#50316)

close pingcap/tidb#50312, close pingcap/tidb#50315
---
 br/pkg/restore/data.go | 42 +-----------------------------------------
 1 file changed, 1 insertion(+), 41 deletions(-)

diff --git a/br/pkg/restore/data.go b/br/pkg/restore/data.go
index 48f015d80a85e..535ed7e4484f0 100644
--- a/br/pkg/restore/data.go
+++ b/br/pkg/restore/data.go
@@ -139,10 +139,6 @@ func doRecoveryData(ctx context.Context, resolveTS uint64, allStores []*metapb.S
 		return totalRegions, recoveryError{error: err, atStage: StageRecovering}
 	}
 
-	if err := recovery.WaitApply(ctx); err != nil {
-		return totalRegions, recoveryError{error: err, atStage: StageRecovering}
-	}
-
 	if err := recovery.PrepareFlashbackToVersion(ctx, resolveTS, restoreTS-1); err != nil {
 		return totalRegions, recoveryError{error: err, atStage: StageFlashback}
 	}
@@ -227,7 +223,7 @@ func (recovery *Recovery) ReadRegionMeta(ctx context.Context) error {
 	totalStores := len(recovery.allStores)
 	workers := utils.NewWorkerPool(uint(min(totalStores, common.MaxStoreConcurrency)), "Collect Region Meta") // TODO: int overflow?
 
-	// TODO: optimize the ErroGroup when TiKV is panic
+	// TODO: optimize the ErrorGroup when TiKV is panic
 	metaChan := make(chan StoreMeta, 1024)
 	defer close(metaChan)
 
@@ -398,42 +394,6 @@ func (recovery *Recovery) SpawnTiKVShutDownWatchers(ctx context.Context) {
 	go mainLoop()
 }
 
-// WaitApply send wait apply to all tikv ensure all region peer apply log into the last
-func (recovery *Recovery) WaitApply(ctx context.Context) (err error) {
-	eg, ectx := errgroup.WithContext(ctx)
-	totalStores := len(recovery.allStores)
-	workers := utils.NewWorkerPool(uint(min(totalStores, common.MaxStoreConcurrency)), "wait apply")
-
-	for _, store := range recovery.allStores {
-		if err := ectx.Err(); err != nil {
-			break
-		}
-		storeAddr := getStoreAddress(recovery.allStores, store.Id)
-		storeId := store.Id
-
-		workers.ApplyOnErrorGroup(eg, func() error {
-			recoveryClient, conn, err := recovery.newRecoveryClient(ectx, storeAddr)
-			if err != nil {
-				return errors.Trace(err)
-			}
-			defer conn.Close()
-			log.Info("send wait apply to tikv", zap.String("tikv address", storeAddr), zap.Uint64("store id", storeId))
-			req := &recovpb.WaitApplyRequest{StoreId: storeId}
-			_, err = recoveryClient.WaitApply(ectx, req)
-			if err != nil {
-				log.Error("wait apply failed", zap.Uint64("store id", storeId))
-				return errors.Trace(err)
-			}
-
-			recovery.progress.Inc()
-			log.Info("wait apply execution success", zap.Uint64("store id", storeId))
-			return nil
-		})
-	}
-	// Wait for all TiKV instances force leader and wait apply to last log.
-	return eg.Wait()
-}
-
 // prepare the region for flashback the data, the purpose is to stop region service, put region in flashback state
 func (recovery *Recovery) PrepareFlashbackToVersion(ctx context.Context, resolveTS uint64, startTS uint64) (err error) {
 	retryState := utils.InitialRetryState(utils.FlashbackRetryTime, utils.FlashbackWaitInterval, utils.FlashbackMaxWaitInterval)