5 suggestions for improving your Ruby code to be better optimized for performance

January 11, 2023
For your apps to function properly and effectively, Ruby code performance optimization is crucial. This article will examine five recommendations for improving the performance of Ruby programming, each with corresponding code examples. 

1. Implement the Ruby profiler: You can use the Ruby profiler to find the parts of your code that are using up the most time and resources. You may identify the areas of your code that are creating bottlenecks and optimize them by utilizing the profiler. 
You must include profiling lines in your code and require the "profiler" library in order to use the profiler. For instance, you can carry out the following if you want to profile the "fibonacci" method:
require 'profiler'

def fibonacci(n)
  if n < 2
    fibonacci(n - 1) + fibonacci(n - 2)


his will send a report to STDERR that includes the time and the number of times the "fibonacci" method was used for each line. You may determine which lines are using the most time from the report and adjust them accordingly. 

2. Use efficient data structures and algorithms: 
The performance of your code can be greatly improved by selecting the appropriate data structure and method. For instance, lookups can be made more faster by using a hash table rather than an array. Utilizing algorithms with the best time complexity for the issue you're trying to solve is also crucial.

For instance, let's say you have a collection of terms and want to determine which word is the most prevalent. Finding the term with the highest frequency can be done by using a hash table to hold the frequency of each word. Here is an illustration of how to accomplish it:

def most_common_word(words)
  word_counts = {}
  words.each do |word|
    if word_counts.has_key?(word)
      word_counts[word] += 1
      word_counts[word] = 1
  word_counts.max_by { |word, count| count }

This function is quicker than sorting the words in an array by frequency, which would take more time and have an O(n) time complexity (n log n). 

3. Results caching: If a component of your code performs an action that takes a while, you might want to think about caching the results so that the operation doesn't have to be done each time. In particular, if the operation is frequently called, this can help your code run more quickly.

Imagine, for instance, that you have a function that creates a report using information from a database. You can cache the results to save yourself from having to generate the report repeatedly because this action might take some time. Here is an example utilizing the Rails 'Rails.cache' package to accomplish this: 

def generate_report
  report = Rails.cache.fetch('report', expires_in: 1.hour) do
    data = fetch_data_from_database

The report will be generated by this code, and it will be kept in the cache for an hour. This can greatly enhance the efficiency of your code because subsequent calls to the "generate report" method will return the cached report rather than creating a new one.

4. Avoid creating unused objects: 
Ruby can be expensive to perform when new objects are created. Avoid generating unused objects and reuse them as much as you can to make your code as efficient as possible. 
Consider a loop that generates a new string object with each iteration. This can be inefficient because memory must be allocated and the object's constructor must be called in order to create a new string object. Instead, you can reuse the same string object and make changes to it each time, as in this example:

def process_data(data)
	result = ''
	data.each do |item|
		result << "#{item.name}: #{item.value}\n"

As opposed to producing a new string object for every iteration, in this example the "result" string is produced once and updated on each iteration.

5. Utilize gems carefully: 
Adding functionality to your Ruby apps is made possible through gems, but it's crucial to use them carefully. Before including any gems in your application, it's crucial to select the ones that are most pertinent to your requirements and verify their performance. Some gems can be resource-intensive.
As an illustration, let's say you need to parse a sizable XML file and you're thinking about utilizing the "Nokogiri" gem. You should evaluate its performance before using it and contrast it with alternative solutions, such as the "REXML" library. This can be accomplished by timing how long it takes for each option to parse the file and selecting the one that works the best.

require 'nokogiri'
require 'rexml/document'
def parse_with_nokogiri
def parse_with_rexml

Measure how long it takes for each option to parse the file.

require 'benchmark'
nokogiri_time = Benchmark.realtime { parse_with_nokogiri }
puts "Nokogiri: #{nokogiri_time}"
rexml_time = Benchmark.realtime { parse_with_rexml }
puts "REXML: #{rexml_time}"

These recommendations can help your Ruby code run more efficiently and make sure your apps are stable. Coding is fun!