Remove line profiler from performance bar

1. The output isn't great. It can be hard to find hotspots and, even
   when you do find them, to find why those are hotspots.
2. It uses some jQuery-specific frontend code which we can remove now
   that we don't have this any more.
3. It's only possible to profile the initial request, not any subsequent
   AJAX requests.

Gemfile

@@ -297,7 +297,6 @@ gem 'batch-loader', '~> 1.4.0'
 # Perf bar
 gem 'peek', '~> 1.0.1'
 gem 'peek-gc', '~> 0.0.2'
-gem 'peek-rblineprof', '~> 0.2.0'
 
 # Memory benchmarks
 gem 'derailed_benchmarks', require: false

Gemfile.lock

@@ -643,9 +643,6 @@ GEM
       railties (>= 4.0.0)
     peek-gc (0.0.2)
       peek
-    peek-rblineprof (0.2.0)
-      peek
-      rblineprof
     pg (1.1.4)
     po_to_json (1.0.1)
       json (>= 1.6.0)
@@ -1177,7 +1174,6 @@ DEPENDENCIES
   org-ruby (~> 0.9.12)
   peek (~> 1.0.1)
   peek-gc (~> 0.0.2)
-  peek-rblineprof (~> 0.2.0)
   pg (~> 1.1)
   premailer-rails (~> 1.9.7)
   prometheus-client-mmap (~> 0.9.8)

app/assets/javascripts/performance_bar/components/performance_bar_app.vue

 <script>
-import $ from 'jquery';
 import { glEmojiTag } from '~/emoji';
 
 import detailedMetric from './detailed_metric.vue';
@@ -28,10 +27,6 @@ export default {
       type: String,
       required: true,
     },
-    profileUrl: {
-      type: String,
-      required: true,
-    },
   },
   detailedMetrics: [
     {
@@ -74,9 +69,6 @@ export default {
     initialRequest() {
       return this.currentRequestId === this.requestId;
     },
-    lineProfileModal() {
-      return $('#modal-peek-line-profile');
-    },
     hasHost() {
       return this.currentRequest && this.currentRequest.details && this.currentRequest.details.host;
     },
@@ -90,10 +82,6 @@ export default {
   },
   mounted() {
     this.currentRequest = this.requestId;
-
-    if (this.lineProfileModal.length) {
-      this.lineProfileModal.modal('toggle');
-    }
   },
   methods: {
     changeCurrentRequest(newRequestId) {
@@ -124,17 +112,6 @@ export default {
         :header="metric.header"
         :keys="metric.keys"
       />
-      <div v-if="initialRequest" id="peek-view-rblineprof" class="view">
-        <button
-          v-if="lineProfileModal.length"
-          class="btn-link btn-blank"
-          data-toggle="modal"
-          data-target="#modal-peek-line-profile"
-        >
-          {{ s__('PerformanceBar|profile') }}
-        </button>
-        <a v-else :href="profileUrl">{{ s__('PerformanceBar|profile') }}</a>
-      </div>
       <div id="peek-view-gc" class="view">
         <span v-if="currentRequest.details" class="bold">
           <span title="Invoke Time">{{ currentRequest.details.gc.gc_time }}</span

app/assets/stylesheets/performance_bar.scss

 @import 'framework/variables';
 @import 'framework/variables_overrides';
-@import 'peek/views/rblineprof';
 
 #js-peek {
   position: fixed;
@@ -128,13 +127,3 @@
 #modal-peek-pg-queries-content {
   color: $black;
 }
-
-.peek-rblineprof-file {
-  pre.duration {
-    width: 280px;
-  }
-
-  .data {
-    overflow: visible;
-  }
-}

app/controllers/concerns/with_performance_bar.rb

@@ -3,10 +3,6 @@
 module WithPerformanceBar
   extend ActiveSupport::Concern
 
-  included do
-    include Peek::Rblineprof::CustomControllerHelpers
-  end
-
   def peek_enabled?
     return false unless Gitlab::PerformanceBar.enabled?(current_user)
 

app/views/peek/_bar.html.haml

@@ -2,6 +2,5 @@
 
 #js-peek{ data: { env: Peek.env,
          request_id: Peek.request_id,
-         peek_url: "#{peek_routes_path}/results",
-         profile_url: url_for(safe_params.merge(lineprofiler: 'true')) },
+         peek_url: "#{peek_routes_path}/results" },
          class: Peek.env }

changelogs/unreleased/remove-line-profile-from-performance-bar.yml

+---
+title: Remove line profiler from performance bar
+merge_request:
+author:
+type: removed

config/initializers/peek.rb

@@ -7,7 +7,6 @@ Rails.application.config.peek.adapter = :redis, { client: ::Redis.new(Gitlab::Re
 Peek.into Peek::Views::Host
 Peek.into Peek::Views::ActiveRecord
 Peek.into Peek::Views::Gitaly
-Peek.into Peek::Views::Rblineprof
 Peek.into Peek::Views::RedisDetailed
 Peek.into Peek::Views::Rugged
 Peek.into Peek::Views::GC

doc/administration/monitoring/performance/performance_bar.md

@@ -14,8 +14,6 @@ It allows you to see (from left to right):
   ![Gitaly profiling using the Performance Bar](img/performance_bar_gitaly_calls.png)
 - time taken and number of [Rugged] calls, click through for details of these calls
   ![Rugged profiling using the Performance Bar](img/performance_bar_rugged_calls.png)
-- profile of the code used to generate the page, line by line. In the profile view, the numbers in the left panel represent wall time, cpu time, and number of calls (based on [rblineprof](https://github.com/tmm1/rblineprof)).
-  ![Line profiling using the Performance Bar](img/performance_bar_line_profiling.png)
 - time taken and number of Redis calls, click through for details of these calls
   ![Redis profiling using the Performance Bar](img/performance_bar_redis_calls.png)
 - time taken and number of Ruby GC calls

lib/peek/rblineprof/custom_controller_helpers.rb

-# frozen_string_literal: true
-
-module Peek
-  module Rblineprof
-    module CustomControllerHelpers
-      extend ActiveSupport::Concern
-
-      # This will become useless once https://github.com/peek/peek-rblineprof/pull/5
-      # is merged
-      def pygmentize(file_name, code, lexer = nil)
-        if lexer.present?
-          Gitlab::Highlight.highlight(file_name, code)
-        else
-          "<pre>#{Rack::Utils.escape_html(code)}</pre>"
-        end
-      end
-
-      # rubocop:disable all
-      def inject_rblineprof
-        ret = nil
-        profile = lineprof(rblineprof_profiler_regex) do
-          ret = yield
-        end
-
-        if response.content_type =~ %r|text/html|
-          sort = params[:lineprofiler_sort]
-          mode = params[:lineprofiler_mode] || 'cpu'
-          min  = (params[:lineprofiler_min] || 5).to_i * 1000
-          summary = params[:lineprofiler_summary]
-
-          # Sort each file by the longest calculated time
-          per_file = profile.map do |file, lines|
-            total, child, excl, total_cpu, child_cpu, excl_cpu = lines[0]
-
-            wall = summary == 'exclusive' ? excl : total
-            cpu  = summary == 'exclusive' ? excl_cpu : total_cpu
-            idle = summary == 'exclusive' ? (excl - excl_cpu) : (total - total_cpu)
-
-            [
-              file, lines,
-              wall, cpu, idle,
-              sort == 'idle' ? idle : sort == 'cpu' ? cpu : wall
-            ]
-          end.sort_by{ |a,b,c,d,e,f| -f }
-
-          output = ["<div class='modal-dialog modal-xl'><div class='modal-content'>"]
-          output << "<div class='modal-header'>"
-          output << "<h4>Line profiling: #{human_description(params[:lineprofiler])}</h4>"
-          output << "<button class='close' type='button' data-dismiss='modal' aria-label='close'><span aria-hidden='true'>&times;</span></button>"
-          output << "</div>"
-          output << "<div class='modal-body'>"
-
-          per_file.each do |file_name, lines, file_wall, file_cpu, file_idle, file_sort|
-            output << "<div class='peek-rblineprof-file'><div class='heading'>"
-
-            show_src = file_sort > min
-            tmpl = show_src ? "<a href='#' class='js-lineprof-file'>%s</a>" : "%s"
-
-            if mode == 'cpu'
-              output << sprintf("<span class='duration'>% 8.1fms + % 8.1fms</span> #{tmpl}", file_cpu / 1000.0, file_idle / 1000.0, file_name.sub(Rails.root.to_s + '/', ''))
-            else
-              output << sprintf("<span class='duration'>% 8.1fms</span> #{tmpl}", file_wall/1000.0, file_name.sub(Rails.root.to_s + '/', ''))
-            end
-
-            output << "</div>" # .heading
-
-            next unless show_src
-
-            output << "<div class='data'>"
-            code = []
-            times = []
-            File.readlines(file_name).each_with_index do |line, i|
-              code << line
-              wall, cpu, calls = lines[i + 1]
-
-              if calls && calls > 0
-                if mode == 'cpu'
-                  idle = wall - cpu
-                  times << sprintf("% 8.1fms + % 8.1fms (% 5d)", cpu / 1000.0, idle / 1000.0, calls)
-                else
-                  times << sprintf("% 8.1fms (% 5d)", wall / 1000.0, calls)
-                end
-              else
-                times << ' '
-              end
-            end
-            output << "<pre class='duration'>#{times.join("\n")}</pre>"
-            # The following line was changed from
-            # https://github.com/peek/peek-rblineprof/blob/8d3b7a283a27de2f40abda45974516693d882258/lib/peek/rblineprof/controller_helpers.rb#L125
-            # This will become useless once https://github.com/peek/peek-rblineprof/pull/16
-            # is merged and is implemented.
-            output << "<pre class='code highlight white'>#{pygmentize(file_name, code.join, 'ruby')}</pre>"
-            output << "</div></div>" # .data then .peek-rblineprof-file
-          end
-
-          output << "</div></div></div>"
-
-          response.body += "<div class='modal' id='modal-peek-line-profile' tabindex=-1>#{output.join}</div>".html_safe
-        end
-
-        ret
-      end
-
-      private
-
-      def human_description(lineprofiler_param)
-        case lineprofiler_param
-        when 'app'
-          'app/ & lib/'
-        when 'views'
-          'app/view/'
-        when 'gems'
-          'vendor/gems'
-        when 'all'
-          'everything in Rails.root'
-        when 'stdlib'
-          'everything in the Ruby standard library'
-        else
-          'app/, config/, lib/, vendor/ & plugin/'
-        end
-      end
-    end
-  end
-end

lib/peek/views/redis_detailed.rb

@@ -22,7 +22,7 @@ module Gitlab
         detail_store << {
           cmd: args.first,
           duration: duration,
-          backtrace: Gitlab::Profiler.clean_backtrace(caller)
+          backtrace: ::Gitlab::Profiler.clean_backtrace(caller)
         }
       end
 

locale/gitlab.pot

@@ -7604,9 +7604,6 @@ msgstr ""
 msgid "PerformanceBar|SQL queries"
 msgstr ""
 
-msgid "PerformanceBar|profile"
-msgstr ""
-
 msgid "PerformanceBar|trace"
 msgstr ""
 

vendor/licenses.csv

@@ -816,7 +816,6 @@ pbkdf2,3.0.14,MIT
 peek,1.0.1,MIT
 peek-gc,0.0.2,MIT
 peek-mysql2,1.1.0,MIT
-peek-rblineprof,0.2.0,MIT
 peek-redis,1.2.0,MIT
 pg,0.18.4,"BSD,ruby,GPL"
 pify,3.0.0,MIT