enhance: Avoid unnecesary syncTargetVersion func call after querycoord recover (#34954)

before querycoord stop gracefully, we will save the current target to
meta store and recover it after querycoord start up, to speed the
querycoord's recovery time. but the target version hasn't been recovered
as expected, and it use latest timestamp as current target's version,
which has no effect to querycoord but an unnecessary syncTargetVersion
func call.

This PR recover the correct target version to avoid unnecessary
syncTargetVersion func call

Signed-off-by: Wei Liu <wei.liu@zilliz.com>

internal/querycoordv2/meta/target.go

@@ -73,7 +73,12 @@ func FromPbCollectionTarget(target *querypb.CollectionTarget) *CollectionTarget
 		}
 	}
 
-	return NewCollectionTarget(segments, dmChannels, partitions)
+	return &CollectionTarget{
+		segments:   segments,
+		dmChannels: dmChannels,
+		partitions: typeutil.NewSet(partitions...),
+		version:    target.GetVersion(),
+	}
 }
 
 func (p *CollectionTarget) toPbMsg() *querypb.CollectionTarget {

internal/querycoordv2/meta/target_manager_test.go

@@ -608,6 +608,7 @@ func (suite *TargetManagerSuite) TestRecover() {
 	suite.mgr.SaveCurrentTarget(suite.catalog)
 
 	// clear target in memory
+	version := suite.mgr.current.getCollectionTarget(collectionID).GetTargetVersion()
 	suite.mgr.current.removeCollectionTarget(collectionID)
 	// try to recover
 	suite.mgr.Recover(suite.catalog)
@@ -616,6 +617,7 @@ func (suite *TargetManagerSuite) TestRecover() {
 	suite.NotNil(target)
 	suite.Len(target.GetAllDmChannelNames(), 2)
 	suite.Len(target.GetAllSegmentIDs(), 2)
+	suite.Equal(target.GetTargetVersion(), version)
 
 	// after recover, target info should be cleaned up
 	targets, err := suite.catalog.GetCollectionTargets()