From fa1d8497d26e84ac9641c49035dda04d24eb7e80 Mon Sep 17 00:00:00 2001
From: crazycs520 <crazycs520@gmail.com>
Date: Fri, 23 Feb 2024 17:36:22 +0800
Subject: [PATCH] Don't invalid region when first round cause by deadlineErr
 when using config timeout #1177

Signed-off-by: crazycs520 <crazycs520@gmail.com>
---
 internal/locate/region_request.go        |  6 ++++++
 internal/locate/replica_selector_test.go | 22 ++++++++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/internal/locate/region_request.go b/internal/locate/region_request.go
index 12c0368099..0f29bb4ac4 100644
--- a/internal/locate/region_request.go
+++ b/internal/locate/region_request.go
@@ -785,6 +785,12 @@ func (state *accessFollower) next(bo *retry.Backoffer, selector *replicaSelector
 				}
 				return nil, stateChanged{}
 			}
+			for _, r := range selector.replicas {
+				if r.deadlineErrUsingConfTimeout {
+					// when meet deadline exceeded error, do fast retry without invalidate region cache.
+					return nil, nil
+				}
+			}
 			metrics.TiKVReplicaSelectorFailureCounter.WithLabelValues("exhausted").Inc()
 			selector.invalidateRegion()
 			return nil, nil
diff --git a/internal/locate/replica_selector_test.go b/internal/locate/replica_selector_test.go
index 30bffb0815..4a9f17b3da 100644
--- a/internal/locate/replica_selector_test.go
+++ b/internal/locate/replica_selector_test.go
@@ -184,6 +184,28 @@ func TestReplicaReadAccessPathByCase(t *testing.T) {
 	}
 	s.True(s.runCaseAndCompare(ca))
 
+	// Don't invalid region in accessFollower, since leader meets deadlineExceededErr.
+	ca = replicaSelectorAccessPathCase{
+		reqType:   tikvrpc.CmdGet,
+		readType:  kv.ReplicaReadMixed,
+		staleRead: false,
+		timeout:   time.Second,
+		label:     nil,
+		accessErr: []RegionErrorType{ServerIsBusyErr, ServerIsBusyErr, DeadLineExceededErr},
+		expect: &accessPathResult{
+			accessPath: []string{
+				"{addr: store1, replica-read: true, stale-read: false}",
+				"{addr: store2, replica-read: true, stale-read: false}",
+				"{addr: store3, replica-read: true, stale-read: false}"},
+			respErr:         "",
+			respRegionError: fakeEpochNotMatch,
+			backoffCnt:      0,
+			backoffDetail:   []string{},
+			regionIsValid:   true,
+		},
+	}
+	s.True(s.runCaseAndCompare(ca))
+
 	// Don't invalid region in tryFollowers, since leader meets deadlineExceededErr.
 	ca = replicaSelectorAccessPathCase{
 		reqType:   tikvrpc.CmdGet,