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console_performance_profiling

⚡ Profile Code Snippets with StackProf or Benchmark​

Leverage StackProf or Ruby’s Benchmark in the console to identify performance hotspots in isolated code paths. You can require profiling libraries on the fly and inspect flamegraphs or report summaries directly.

# Inside rails console
require 'stackprof'

StackProf.run(mode: :cpu, out: 'tmp/stackprof-cpu.dump') do
  User.where(active: true).includes(:orders).each do |u|
    u.orders.map(&:total).sum
  end
end

puts "🔥 Dump written to tmp/stackprof-cpu.dump"
# Then visualize with: stackprof tmp/stackprof-cpu.dump --flamegraph > tmp/flamegraph.html

Alternatively, use Benchmark for quick per-iteration insights:

require 'benchmark/ips'

Benchmark.ips do |x|
  x.report("no index") { User.where('created_at > ?', 1.week.ago).to_a }
  x.report("with index") { User.where(created_at: 1.week.ago..Time.current).to_a }
  x.compare!
end