Whitespace

SELECT userid, dbid, left(query, 100), total_time, rows FROM pg_stat_statements WHERE total_time >= 1000 ORDER BY total_time DESC;

Whitespace

Background

Not every app is setup to run capybara tests, but many have an existing testing framework that we'll have to integrate with. Here are some common frameworks we'll come across.

Rspec

If there's no existing testing framework, let's setup this app with rspec, which is preferred.

Whitespace

require "net/http"

def start_server
  # Remove the X to enable the parameters for tuning.
  # These are the default values as of Ruby 2.2.0.
  @child = spawn(<<-EOC.split.join(" "))
    XRUBY_GC_HEAP_FREE_SLOTS=4096
    XRUBY_GC_HEAP_INIT_SLOTS=10000
    XRUBY_GC_HEAP_GROWTH_FACTOR=1.8
    XRUBY_GC_HEAP_GROWTH_MAX_SLOTS=0

Whitespace

-- Heroku has a bunch of awesome queries
-- https://github.com/heroku/heroku-pg-extras/tree/master/commands

-- View slow queries for widgets table
SELECT query, total_time/calls AS avg_time
FROM pg_stat_statements
WHERE query LIKE 'SELECT%'
  AND query LIKE '%widgets%'
ORDER BY avg_time DESC;