executor: keep analyze status remaining time in UTC (pingcap#67229)

close pingcap#67230

Author: 0xPoe

pkg/executor/infoschema_reader.go

@@ -2546,11 +2546,15 @@ func dataForAnalyzeStatusHelper(ctx context.Context, e *memtableRetriever, sctx
 		jobInfo := chunkRow.GetString(3)
 		processedRows := chunkRow.GetInt64(4)
 		var startTime, endTime any
+		// startTime and endTime use the local timezone for displaying.
+		// startTimeUTC is used to calculate the remaining duration of the job.
+		var startTimeUTC *time.Time
 		if !chunkRow.IsNull(5) {
 			t, err := chunkRow.GetTime(5).GoTime(time.UTC)
 			if err != nil {
 				return nil, err
 			}
+			startTimeUTC = &t
 			startTime = types.NewTime(types.FromGoTime(t.In(sctx.GetSessionVars().TimeZone)), mysql.TypeDatetime, 0)
 		}
 		if !chunkRow.IsNull(6) {
@@ -2574,11 +2578,10 @@ func dataForAnalyzeStatusHelper(ctx context.Context, e *memtableRetriever, sctx
 
 		var remainDurationStr, progressDouble, estimatedRowCntStr any
 		if state == statistics.AnalyzeRunning && !strings.HasPrefix(jobInfo, "merge global stats") {
-			startTime, ok := startTime.(types.Time)
-			if !ok {
+			if startTimeUTC == nil {
 				return nil, errors.New("invalid start time")
 			}
-			remainingDuration, progress, estimatedRowCnt, remainDurationErr := getRemainDurationForAnalyzeStatusHelper(ctx, sctx, &startTime,
+			remainingDuration, progress, estimatedRowCnt, remainDurationErr := getRemainDurationForAnalyzeStatusHelper(ctx, sctx, startTimeUTC,
 				dbName, tableName, partitionName, processedRows)
 			if remainDurationErr != nil {
 				logutil.BgLogger().Warn("get remaining duration failed", zap.Error(remainDurationErr))
@@ -2615,16 +2618,13 @@ func dataForAnalyzeStatusHelper(ctx context.Context, e *memtableRetriever, sctx
 
 func getRemainDurationForAnalyzeStatusHelper(
 	ctx context.Context,
-	sctx sessionctx.Context, startTime *types.Time,
+	sctx sessionctx.Context, startTimeUTC *time.Time,
 	dbName, tableName, partitionName string, processedRows int64,
 ) (_ *time.Duration, percentage, totalCnt float64, err error) {
 	remainingDuration := time.Duration(0)
-	if startTime != nil {
-		start, err := startTime.GoTime(time.UTC)
-		if err != nil {
-			return nil, percentage, totalCnt, err
-		}
-		duration := time.Now().UTC().Sub(start)
+	if startTimeUTC != nil {
+		// time.Time.Sub uses the actual instant.
+		duration := time.Since(*startTimeUTC)
 		if intest.InTest {
 			if val := ctx.Value(AnalyzeProgressTest); val != nil {
 				remainingDuration, percentage = calRemainInfoForAnalyzeStatus(ctx, int64(totalCnt), processedRows, duration)

pkg/executor/show_stats_test.go

@@ -399,4 +399,41 @@ func TestShowAnalyzeStatus(t *testing.T) {
 		"merge global stats for test.t2 columns",
 		"analyze table all indexes, all columns with 256 buckets, 100 topn, 1 samplerate",
 	}, jobInfos)
+
+	tk.MustExec("delete from mysql.analyze_jobs")
+	tk.MustExec("drop table if exists t3")
+	tk.MustExec("create table t3 (a int, b int, primary key(a))")
+	tk.MustExec(`insert into t3 values (1, 1), (2, 2)`)
+	tk.MustExec("analyze table t3")
+	tk.MustExec("delete from mysql.analyze_jobs")
+
+	originalTZ := tk.MustQuery("select @@time_zone").Rows()[0][0]
+	defer func() {
+		tk.MustExec("set @@time_zone = ?", originalTZ)
+	}()
+	tk.MustExec("set @@time_zone = '+08:00'")
+	tk.MustExec(`insert into mysql.analyze_jobs (
+		table_schema,
+		table_name,
+		partition_name,
+		job_info,
+		processed_rows,
+		start_time,
+		state,
+		instance
+	) values (
+		'test',
+		't3',
+		'',
+		'analyze table all indexes, all columns with 256 buckets, 100 topn, 1 samplerate',
+		1,
+		CURRENT_TIMESTAMP - INTERVAL 1 MINUTE,
+		'running',
+		'127.0.0.1:4000'
+	)`)
+	rows = tk.MustQuery("show analyze status where table_name = 't3' and state = 'running'").Rows()
+	require.Len(t, rows, 1)
+	remainingDuration, err := time.ParseDuration(rows[0][11].(string))
+	require.NoError(t, err)
+	require.GreaterOrEqual(t, remainingDuration, time.Duration(0))
 }