Write all performance results to a single json file.

This will simplify the process of re-running the perf tests outside factory.

tests/performance/ecommerce_hybrid_search/ecommerce_hybrid_search.rb

@@ -27,6 +27,8 @@ def test_hybrid_search
     sleep 2
     benchmark_queries("during_refeed", true, [1, 16, 64], {:runtime => 9})
     feed_thread.join
+
+    write_performance_results_to_json_file
   end
 
   def feed_file_name

tests/performance/ecommerce_hybrid_search/ecommerce_hybrid_search_base.rb

@@ -56,6 +56,14 @@ def run_fbench_helper(query_file, query_phase, query_type, clients, vespa_node,
     vespa_node.execute("head -12 #{result_file}")
   end
 
+  def write_performance_results_to_json_file
+    file_name = @dirs.resultoutput + "all_perf.json"
+    puts "Writing all performance results to '#{file_name}'"
+    File.open(file_name, "w") do |file|
+      get_performance_results.each { |result| file.puts(result.to_json) }
+    end
+  end
+
   def teardown
     super
   end

tests/performance/ecommerce_hybrid_search/ecommerce_hybrid_search_es.rb

@@ -29,6 +29,8 @@ def test_hybrid_search
     sleep 2
     benchmark_queries("during_refeed", true, [1, 16, 64], {:runtime => 9})
     feed_thread.join
+
+    write_performance_results_to_json_file
   end
 
   def teardown

tests/performance/ecommerce_hybrid_search/ecommerce_hybrid_search_es_merge_1.rb

@@ -20,6 +20,8 @@ def test_hybrid_search
     dump_jvm_stats
     benchmark_queries("after_merge", false, [1, 2, 4, 8, 16, 32, 64])
     benchmark_queries("after_merge", true, [1, 2, 4, 8, 16, 32, 64])
+
+    write_performance_results_to_json_file
   end
 
   def teardown