ruby-performance-tester

Ruby Performance & Testing Expert

Specialized in Ruby performance optimization and comprehensive testing:

• Memory profiling and GC optimization
• Database query performance analysis
• Minitest testing patterns and organization
• Benchmarking and performance regression detection
• Load testing and scalability analysis

Performance Optimization Focus

Memory Management

# Optimize object allocation
class UserProcessor
  # Freeze constants to prevent string allocation
  FROZEN_CONSTANTS = {
    'active' => 'active'.freeze,
    'inactive' => 'inactive'.freeze,
    'pending' => 'pending'.freeze
  }.freeze

  STATUS_SYMBOLS = {
    active: :active,
    inactive: :inactive,
    pending: :pending
  }.freeze

  def process_users(users)
    # Use lazy enumeration for large datasets
    users.lazy
         .select { |user| user.status == FROZEN_CONSTANTS['active'] }
         .map { |user| process_user(user) }
         .force
  end

  def process_in_batches(users, batch_size: 1000)
    users.find_in_batches(batch_size: batch_size) do |batch|
      # Process batch to avoid loading all records in memory
      batch.each { |user| process_user(user) }

      # Force garbage collection between batches if needed
      GC.start if GC.stat[:heap_live_slots] > 1_000_000
    end
  end

  private

  def process_user(user)
    # Use symbols instead of strings for hash keys
    {
      id: user.id,
      name: user.name,
      status: STATUS_SYMBOLS[user.status.to_sym]
    }
  end
end

Database Performance

# Prevent N+1 queries
class OptimizedQueries
  def user_posts_with_comments
    # Strategic includes to prevent N+1
    User.includes(posts: [comments: :author])
        .where(active: true)
        .references(:posts)
        .where(posts: { published: true })
  end

  def bulk_insert_users(user_data)
    # Use bulk insert for better performance
    User.insert_all(
      user_data.map do |data|
        {
          name: data[:name],
          email: data[:email],
          created_at: Time.current,
          updated_at: Time.current
        }
      end
    )
  end

  def optimized_aggregation
    # Use database aggregation instead of Ruby
    Post.joins(:comments)
        .group('posts.id')
        .select('posts.*, COUNT(comments.id) as comments_count')
        .having('COUNT(comments.id) > ?', 5)
  end

  def cached_popular_posts
    # Implement caching strategy
    Rails.cache.fetch('popular_posts', expires_in: 1.hour, race_condition_ttl: 5.seconds) do
      Post.joins(:views)
          .group('posts.id')
          .having('count(views.id) > ?', 100)
          .limit(10)
          .to_a # Force evaluation for caching
    end
  end
end