Add backtrace to Gitaly performance bar

This adds the backtrace to a table to show exactly where the Gitaly call
was made to make it easier to understand where the call originated.

This change also collapses the details in the same row to improve the
usability when there is a backtrace.

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

 <script>
 import GlModal from '~/vue_shared/components/gl_modal.vue';
+import Icon from '~/vue_shared/components/icon.vue';
 export default {
   components: {
     GlModal,
+    Icon,
   },
   props: {
     currentRequest: {
@@ -57,9 +59,31 @@ export default {
         <template v-if="detailsList.length">
           <tr v-for="(item, index) in detailsList" :key="index">
             <td>
-              <strong>{{ item.duration }}ms</strong>
+              <span>{{ item.duration }}ms</span>
+            </td>
+            <td>
+              <div class="js-toggle-container">
+                <div
+                  v-for="(key, keyIndex) in keys"
+                  :key="key"
+                  class="break-word"
+                  :class="{ 'mb-3 bold': keyIndex == 0 }"
+                >
+                  {{ item[key] }}
+                  <button
+                    v-if="keyIndex == 0 && item.backtrace"
+                    class="text-expander js-toggle-button"
+                    type="button"
+                    :aria-label="__('Toggle backtrace')"
+                  >
+                    <icon :size="12" name="ellipsis_h" />
+                  </button>
+                </div>
+                <pre v-if="item.backtrace" class="backtrace-row js-toggle-content mt-2">{{
+                  item.backtrace
+                }}</pre>
+              </div>
             </td>
-            <td v-for="key in keys" :key="key" class="break-word">{{ item[key] }}</td>
           </tr>
         </template>
         <template v-else>

app/assets/stylesheets/performance_bar.scss

@@ -79,8 +79,12 @@
   table {
     color: $black;
-    strong {
-      color: $black;
+    td {
+      vertical-align: top;
+    }
+
+    .backtrace-row {
+      display: none;
     }
   }

changelogs/unreleased/sh-add-gitaly-backtrace.yml

+---
+title: Add backtrace to Gitaly performance bar
+merge_request: 27345
+author:
+type: other

lib/gitlab/gitaly_client.rb

@@ -165,7 +165,10 @@ module Gitlab
         current_transaction_labels.merge(gitaly_service: service.to_s, rpc: rpc.to_s),
         duration)
-      add_call_details(feature: "#{service}##{rpc}", duration: duration, request: request_hash, rpc: rpc)
+      if peek_enabled?
+        add_call_details(feature: "#{service}##{rpc}", duration: duration, request: request_hash, rpc: rpc,
+                         backtrace: Gitlab::Profiler.clean_backtrace(caller))
+      end
     end
     def self.query_time
@@ -350,15 +353,17 @@ module Gitlab
       Gitlab::SafeRequestStore["gitaly_call_permitted"] = 0
     end
-    def self.add_call_details(details)
-      return unless Gitlab::SafeRequestStore[:peek_enabled]
+    def self.peek_enabled?
+      Gitlab::SafeRequestStore[:peek_enabled]
+    end
+    def self.add_call_details(details)
       Gitlab::SafeRequestStore['gitaly_call_details'] ||= []
       Gitlab::SafeRequestStore['gitaly_call_details'] << details
     end
     def self.list_call_details
-      return [] unless Gitlab::SafeRequestStore[:peek_enabled]
+      return [] unless peek_enabled?
       Gitlab::SafeRequestStore['gitaly_call_details'] || []
     end

lib/gitlab/profiler.rb

@@ -16,7 +16,11 @@ module Gitlab
       ee/lib/gitlab/middleware/
       lib/gitlab/performance_bar/
       lib/gitlab/request_profiler/
+      lib/gitlab/query_limiting/
+      lib/gitlab/tracing/
       lib/gitlab/profiler.rb
+      lib/gitlab/correlation_id.rb
+      lib/gitlab/webpack/dev_server_middleware.rb
     ].freeze
     # Takes a URL to profile (can be a fully-qualified URL, or an absolute path)

locale/gitlab.pot

@@ -9559,6 +9559,9 @@ msgstr ""
 msgid "Toggle Sidebar"
 msgstr ""
+msgid "Toggle backtrace"
+msgstr ""
+
 msgid "Toggle comments for this file"
 msgstr ""

spec/javascripts/performance_bar/components/detailed_metric_spec.js

@@ -27,8 +27,8 @@ describe('detailedMetric', () => {
   describe('when the current request has details', () => {
     const requestDetails = [
-      { duration: '100', feature: 'find_commit', request: 'abcdef' },
-      { duration: '23', feature: 'rebase_in_progress', request: '' },
+      { duration: '100', feature: 'find_commit', request: 'abcdef', backtrace: ['hello', 'world'] },
+      { duration: '23', feature: 'rebase_in_progress', request: '', backtrace: ['world', 'hello'] },
     ];
     beforeEach(() => {
@@ -54,9 +54,11 @@ describe('detailedMetric', () => {
     });
     it('adds a modal with a table of the details', () => {
-      vm.$el.querySelectorAll('.performance-bar-modal td strong').forEach((duration, index) => {
-        expect(duration.innerText).toContain(requestDetails[index].duration);
-      });
+      vm.$el
+        .querySelectorAll('.performance-bar-modal td:nth-child(1)')
+        .forEach((duration, index) => {
+          expect(duration.innerText).toContain(requestDetails[index].duration);
+        });
       vm.$el
         .querySelectorAll('.performance-bar-modal td:nth-child(2)')
@@ -65,10 +67,16 @@ describe('detailedMetric', () => {
         });
       vm.$el
-        .querySelectorAll('.performance-bar-modal td:nth-child(3)')
+        .querySelectorAll('.performance-bar-modal td:nth-child(2)')
         .forEach((request, index) => {
-          expect(request.innerText).toEqual(requestDetails[index].request);
+          expect(request.innerText).toContain(requestDetails[index].request);
         });
+
+      expect(vm.$el.querySelector('.text-expander.js-toggle-button')).not.toBeNull();
+
+      vm.$el.querySelectorAll('.performance-bar-modal td:nth-child(2)').forEach(request => {
+        expect(request.innerText).toContain('world');
+      });
     });
     it('displays the metric name', () => {