moved throttling into the controller. if we hit the throttling

threshhold, a message is shown indicating we didn't perform the search

app/controllers/projects/commit_controller.rb

@@ -56,8 +56,11 @@ class Projects::CommitController < Projects::ApplicationController
   end
 
   def branches
-    @branches = @project.repository.branch_names_contains(commit.id, 1000)
-    @tags = @project.repository.tag_names_contains(commit.id, 1000)
+    # branch_names_contains/tag_names_contains can take a long time when there are thousands of
+    # branches/tags - each `git branch --contains xxx` request can consume a cpu core.
+    # so only do the query when there are a manageable number of branches/tags
+    @branches = @project.repository.branch_count > 1000 ? [:limit_exceeded] : @project.repository.branch_names_contains(commit.id)
+    @tags = @project.repository.tag_count > 1000 ? [:limit_exceeded] : @project.repository.tag_names_contains(commit.id)
     render layout: false
   end
 

app/helpers/commits_helper.rb

@@ -60,23 +60,33 @@ module CommitsHelper
     branches.include?(project.default_branch) ? branches.delete(project.default_branch) : branches.pop
   end
 
+  # returns a link formatted as a commit branch link
+  def commit_branch_link(url, text)
+    link_to(url, class: 'label label-gray ref-name') do
+      icon('code-fork') + " #{text}"
+    end
+  end
+
   # Returns the sorted alphabetically links to branches, separated by a comma
   def commit_branches_links(project, branches)
     branches.sort.map do |branch|
-      link_to(project_ref_path(project, branch), class: "label label-gray ref-name") do
-        icon('code-fork') + " #{branch}"
+      commit_branch_link(project_ref_path(project, branch), branch)
+    end.join(' ').html_safe
+  end
+
+  # returns a link formatted as a commit tag link
+  def commit_tag_link(url, text)
+    link_to(url, class: 'label label-gray ref-name') do
+      icon('tag') + " #{text}"
     end
-    end.join(" ").html_safe
   end
 
   # Returns the sorted links to tags, separated by a comma
   def commit_tags_links(project, tags)
     sorted = VersionSorter.rsort(tags)
     sorted.map do |tag|
-      link_to(project_ref_path(project, tag), class: "label label-gray ref-name") do
-        icon('tag') + " #{tag}"
-      end
-    end.join(" ").html_safe
+      commit_tag_link(project_ref_path(project, tag), tag)
+    end.join(' ').html_safe
   end
 
   def link_to_browse_code(project, commit)

app/models/repository.rb

@@ -715,12 +715,12 @@ class Repository
     end
   end
 
-  def branch_names_contains(sha, limit = nil)
-    limit && branch_count > limit ? [] : refs_contains_sha('branch', sha)
+  def branch_names_contains(sha)
+    refs_contains_sha('branch', sha)
   end
 
-  def tag_names_contains(sha, limit = nil)
-    limit && tag_count > limit ? [] : refs_contains_sha('tag', sha)
+  def tag_names_contains(sha)
+    refs_contains_sha('tag', sha)
   end
 
   def local_branches

app/views/projects/commit/branches.html.haml

-- if @branches.any? || @tags.any?
+- if @branches.any?
   - branch = commit_default_branch(@project, @branches)
-  = link_to(project_ref_path(@project, branch), class: "label label-gray ref-name") do
-    = icon('code-fork')
-    = branch
+  - if branch == :limit_exceeded
+    = commit_branch_link('#', _('Too many branches to search'))
+  - else
+    = commit_branch_link(project_ref_path(@project, branch), branch)
 
-  -# `commit_default_branch` deletes the default branch from `@branches`,
-  -# so only render this if we have more branches left
-  - if @branches.any? || @tags.any?
+-# `commit_default_branch` deletes the default branch from `@branches`,
+-# so only render this if we have more branches or tags left
+- if @branches.any? || @tags.any?
   %span
     = link_to "…", "#", class: "js-details-expand label label-gray"
 
     %span.js-details-content.hide
       = commit_branches_links(@project, @branches) if @branches.any?
-        = commit_tags_links(@project, @tags) if @tags.any?
+      - if @tags.first == :limit_exceeded
+        = commit_tag_link('#', _('Too many tags to search'))
+      - elsif @tags.any?
+        = commit_tags_links(@project, @tags)