query: Disable downsampling by default.

(Details #376) Signed-off-by: Bartek Plotka <bwplotka@gmail.com>
thanos-io · Jul 5, 2018 · 972a52e · 972a52e
1 parent eaf7756
commit 972a52e
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Showing 4 changed files with 57 additions and 46 deletions.
diff --git a/cmd/thanos/query.go b/cmd/thanos/query.go
@@ -55,6 +55,9 @@ func registerQuery(m map[string]setupFunc, app *kingpin.Application, name string
 	stores := cmd.Flag("store", "Addresses of statically configured store API servers (repeatable).").
 		PlaceHolder("<store>").Strings()
 
+	enableAutodownsampling := cmd.Flag("query.auto-downsampling", "Enable automatic adjustment (step / 5) to what source of data should be used in store gateways if no max_source_resolution param is specified. ").
+		Default("false").Bool()
+
 	m[name] = func(g *run.Group, logger log.Logger, reg *prometheus.Registry, tracer opentracing.Tracer, _ bool) error {
 		peer, err := newPeerFn(logger, reg, true, *httpAdvertiseAddr, true)
 		if err != nil {
@@ -87,6 +90,7 @@ func registerQuery(m map[string]setupFunc, app *kingpin.Application, name string
 			peer,
 			selectorLset,
 			*stores,
+			*enableAutodownsampling,
 		)
 	}
 }
@@ -141,6 +145,7 @@ func runQuery(
 	peer *cluster.Peer,
 	selectorLset labels.Labels,
 	storeAddrs []string,
+	enableAutodownsampling bool,
 ) error {
 	var staticSpecs []query.StoreSpec
 	for _, addr := range storeAddrs {
@@ -208,7 +213,7 @@ func runQuery(
 		router := route.New()
 		ui.New(logger, nil).Register(router)
 
-		api := v1.NewAPI(logger, reg, engine, queryableCreator)
+		api := v1.NewAPI(logger, reg, engine, queryableCreator, enableAutodownsampling)
 		api.Register(router.WithPrefix("/api/v1"), tracer, logger)
 
 		mux := http.NewServeMux()

diff --git a/pkg/query/api/v1.go b/pkg/query/api/v1.go
@@ -101,10 +101,10 @@ type API struct {
 	queryableCreate query.QueryableCreator
 	queryEngine     *promql.Engine
 
-	instantQueryDuration prometheus.Histogram
-	rangeQueryDuration   prometheus.Histogram
-
-	now func() time.Time
+	instantQueryDuration   prometheus.Histogram
+	rangeQueryDuration     prometheus.Histogram
+	enableAutodownsampling bool
+	now                    func() time.Time
 }
 
 // NewAPI returns an initialized API type.
@@ -113,6 +113,7 @@ func NewAPI(
 	reg *prometheus.Registry,
 	qe *promql.Engine,
 	c query.QueryableCreator,
+	enableAutodownsampling bool,
 ) *API {
 	instantQueryDuration := prometheus.NewHistogram(prometheus.HistogramOpts{
 		Name: "thanos_query_api_instant_query_duration_seconds",
@@ -134,12 +135,13 @@ func NewAPI(
 		rangeQueryDuration,
 	)
 	return &API{
-		logger:               logger,
-		queryEngine:          qe,
-		queryableCreate:      c,
-		instantQueryDuration: instantQueryDuration,
-		rangeQueryDuration:   rangeQueryDuration,
-		now:                  time.Now,
+		logger:                 logger,
+		queryEngine:            qe,
+		queryableCreate:        c,
+		instantQueryDuration:   instantQueryDuration,
+		rangeQueryDuration:     rangeQueryDuration,
+		enableAutodownsampling: enableAutodownsampling,
+		now: time.Now,
 	}
 }
 
@@ -277,7 +279,11 @@ func (api *API) queryRange(r *http.Request) (interface{}, []error, *apiError) {
 		return nil, nil, &apiError{errorBadData, err}
 	}
 
-	maxSourceResolution := step / 5 // By default fit at least 5 samples between steps.
+	maxSourceResolution := 0 * time.Second
+	if api.enableAutodownsampling {
+		// If no max_source_resolution is specified fit at least 5 samples between steps.
+		maxSourceResolution = step / 5
+	}
 	if val := r.FormValue("max_source_resolution"); val != "" {
 		maxSourceResolution, err = parseDuration(val)
 		if err != nil {