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View gist:43d584c70707407cf61998437a61a772
require 'benchmark/ips'
Benchmark.ips do |x|
x.config(time: 60, warmup: 5)
x.config(stats: :bootstrap, confidence: 95)'binstub') { `bin/rspec -v`}'bundle exec') {`bundle exec rspec -v `}'direct') {`rspec -v `}
fcheung / results
Created Jul 27, 2019
unpack cookie benchmark
View results
require 'benchmark/ips'
def reverse(session_data)
digest, session_data = session_data.reverse.split('--', 2)
digest.reverse! if digest
session_data.reverse! if session_data
[session_data, digest]
def index(session_data)
fcheung / get_mem.rb
Created Jul 5, 2019
View get_mem.rb
require 'ffi'
require 'get_process_mem'
require 'benchmark/ips'
module MemoryInfo
extend FFI::Library
ffi_lib 'c'
attach_function :mach_task_self, [], :__darwin_mach_port_t
attach_function :task_info,
fcheung /
Created Nov 27, 2017
changes observed from ruby mongo 1.x to 2.x

#Updating from mongo ruby drive 1.x to 2.x

We've recently been belatedly migrating to the 2.x series of the mongo ruby driver. At least in part this is because there's very little documentation out there on what has changed, except that there is no backwards compatibility. This post is a list of issues that we came across - I expect it is by no means exhaustive


Before you get started, make sure that any dependencies you have are also comaptible with mongo 2.x. For example database_cleaner needs to be 1.5 or higher

View Gemfile (initial)
source ''
gem 'rails', '~>'
gem 'devise', '~> 3.5.0'
gem 'rspec-rails', '~> 3.4.0'

Keybase proof

I hereby claim:

  • I am fcheung on github.
  • I am frederickcheung ( on keybase.
  • I have a public key whose fingerprint is 9A1B 5755 1E45 1BAE 41D4 8905 C4CD 3D1E B871 B631

To claim this, I am signing this object:

View tr_tree.rb
class Tree
attr_accessor :payload, :children
def initialize(payload, children = [])
@payload = payload
@children = children
def traverse(&block)
yield self
@children.each {|child| child.traverse(&block)}
fcheung / gist:4072448
Created Nov 14, 2012
BritRuby proposal
View gist:4072448

Going Native

We all love ruby, but sometimes ruby is not enough. Whether it be a performance bottleneck, a killer library written in C or some platform specific functionality you just have to have, sometimes you need to drop down a level.

There have been many talks that show how to take the first steps in writing a ruby C extension. This isn't one of them. I propose instead to give an overview of different ways of extending ruby and show what each approach brings to the table. I intend to cover 'classic' C extensions, RubyInline and FFI across a range of ruby implementations.

About me

View challenge#2.rb
class Image
attr_accessor :data
def initialize (data)
@data = data
def image_blur
changes = []
@data.each_with_index do |row, row_index|
View cl1.rb
class Image
attr_accessor :data
def initialize (data)
@data = data
def output
@data.each do |sub|
sub.each do |cell|
print cell