From 50e2524bc2a3750a1f20e221993f0b2cf8939460 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=8C=A0=E5=BF=83=E9=9B=B6=E5=BA=A6?= <97019752@qq.com>
Date: Mon, 5 Sep 2022 16:51:32 +0800
Subject: [PATCH] api prometheus/api/v1/label/../values time  not specified,
 (#3052)

modify default start values
---
 app/vmselect/prometheus/prometheus.go | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/app/vmselect/prometheus/prometheus.go b/app/vmselect/prometheus/prometheus.go
index c5ec39e6b..6b1876ed8 100644
--- a/app/vmselect/prometheus/prometheus.go
+++ b/app/vmselect/prometheus/prometheus.go
@@ -1072,12 +1072,13 @@ func getExportParams(r *http.Request, startTime time.Time) (*commonParams, error
 // - extra_filters[]
 func getCommonParams(r *http.Request, startTime time.Time, requireNonEmptyMatch bool) (*commonParams, error) {
 	deadline := searchutils.GetDeadlineForQuery(r, startTime)
-	start, err := searchutils.GetTime(r, "start", 0)
+	ct := startTime.UnixNano() / 1e6
+	start, err := searchutils.GetTime(r, "start", ct-3*defaultStep)
 	if err != nil {
 		return nil, err
 	}
-	ct := startTime.UnixNano() / 1e6
 	end, err := searchutils.GetTime(r, "end", ct)
+
 	if err != nil {
 		return nil, err
 	}