Fix url property format and use conn. pool

Also update arrivalRate to a max of 100

qa/Rakefile

@@ -27,9 +27,9 @@ task :run_artillery_load_tests do
     end
 
     urls = YAML.safe_load(File.read(urls_file))
-    ENV['HOST_URL'] = urls[:host]
-    ENV['LARGE_ISSUE_URL'] = urls[:large_issue]
-    ENV['LARGE_MR_URL'] = urls[:large_mr]
+    ENV['HOST_URL'] = urls["host"]
+    ENV['LARGE_ISSUE_URL'] = urls["large_issue"]
+    ENV['LARGE_MR_URL'] = urls["large_mr"]
   end
 
   sh('artillery run load/artillery.yml -o report.json')

qa/load/artillery.yml

 config:
   target: "{{ $processEnvironment.HOST_URL }}"
+  http:
+    pool: 10 # All HTTP requests from all virtual users will be sent over the same <pool> connections.
+             # This also means that there is a limit on the number of requests sent per second.
   phases:
-    - duration: 60
-      arrivalRate: 1
+    - duration: 30
+      arrivalRate: 10
       name: "Warm up"
-    - duration: 120
-      arrivalRate: 1
-      rampTo: 50
+    - duration: 90
+      arrivalRate: 10
+      rampTo: 100
       name: "Gradual ramp up"
-    - duration: 60
-      arrivalRate: 50
+    - duration: 90
+      arrivalRate: 100
       name: "Sustained max load"
 scenarios:
   - name: "Visit large issue url"

qa/qa/tools/generate_perf_testdata.rb

@@ -46,7 +46,7 @@ module QA
 
         threads_arr.each(&:join)
         STDOUT.puts "\nURLs: #{@urls}"
-        File.open("urls.yml", "w") { |file| file.puts @urls.to_yaml }
+        File.open("urls.yml", "w") { |file| file.puts @urls.stringify_keys.to_yaml }
         STDOUT.puts "\nDone"
       end