From af0c73720e5cfc104c36923672dafb7de348d2cc Mon Sep 17 00:00:00 2001
From: Bruce Sherrod <bsherrod@users.noreply.github.com>
Date: Thu, 25 Jun 2020 08:51:42 -0700
Subject: [PATCH] fix performance issue in processHistogramLabels() (#25813)

---
 public/app/plugins/datasource/prometheus/language_utils.ts | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/public/app/plugins/datasource/prometheus/language_utils.ts b/public/app/plugins/datasource/prometheus/language_utils.ts
index b8ccdebe4db..098f5909d4c 100644
--- a/public/app/plugins/datasource/prometheus/language_utils.ts
+++ b/public/app/plugins/datasource/prometheus/language_utils.ts
@@ -4,17 +4,16 @@ import { addLabelToQuery } from './add_label_to_query';
 export const RATE_RANGES = ['1m', '5m', '10m', '30m', '1h'];
 
 export const processHistogramLabels = (labels: string[]) => {
-  const result = [];
+  const resultSet: Set<string> = new Set();
   const regexp = new RegExp('_bucket($|:)');
   for (let index = 0; index < labels.length; index++) {
     const label = labels[index];
     const isHistogramValue = regexp.test(label);
     if (isHistogramValue) {
-      if (result.indexOf(label) === -1) {
-        result.push(label);
-      }
+      resultSet.add(label);
     }
   }
+  const result = [...resultSet];
 
   return { values: { __name__: result } };
 };