randito

Deploying to Fly.io with SQLite

Deploying a Phoenix app to Fly.io is a breeze...is what everyone kept telling me. In fairness, I imagine the process would have been breezier had I just used postgres, but all the sqlite and litestream talk has been far too intriguing to ignore. "Wait", you say. "It is just a flat file. How much harder can it be?"

It is easy to make something harder than it should be. It is hard to take something complex and make it truly simple. flyctl launch does an amazing job at providing a simple interface to the utterly complex task of generating deployment resources, especially now that we are living in a containerd (erm, firecracker) world.

This gist is for anyone who, like me, thinks they know better than to read all of the documentation and therefore necessari

randito

sysctl -w fs.file-max=12000500
sysctl -w fs.nr_open=20000500
ulimit -n 4000000
sysctl -w net.ipv4.tcp_mem='10000000 10000000 10000000'
sysctl -w net.ipv4.tcp_rmem='1024 4096 16384'
sysctl -w net.ipv4.tcp_wmem='1024 4096 16384'
sysctl -w net.core.rmem_max=16384
sysctl -w net.core.wmem_max=16384
wget http://packages.erlang-solutions.com/erlang-solutions_1.0_all.deb
sudo dpkg -i erlang-solutions_1.0_all.deb

randito

FROM elixir:slim

# install Node.js (>= 8.0.0) and NPM in order to satisfy brunch.io dependencies
# See https://hexdocs.pm/phoenix/installation.html#node-js-5-0-0
RUN apt-get update -y && \
    apt-get install -y curl git && \
    curl -sL https://deb.nodesource.com/setup_13.x | bash - && \
    apt-get install -y inotify-tools nodejs

WORKDIR /code

randito

Keybase proof

I hereby claim:

• I am randito on github.
• I am randito (https://keybase.io/randito) on keybase.
• I have a public key ASBHQ_4YjXW4eqaOFvMLIE2TxbMD_n-wjIA0AQRuQt7M8wo

To claim this, I am signing this object:

randito

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

randito

# other, self
listen { |other|
  other_name = other.name
}
run { |other|
  puts "Other name"
  puts other.name
  puts "Self name"
  puts self.name

randito

# From: http://emberjs.com/guides/getting-started/creating-a-new-model/
Todos.TodosController = Ember.ArrayController.extend
  actions:
    createTodo: ->
      title = @get 'newTitle'
      return unless title.trim()

      @set 'newTitle', ''
      @store.createRecord 'todo',
        title: title

randito

#!/usr/bin/env ruby -wKU

regexp = /\w+-*\w+/  # i.e hugger-mugger
triplets = ::DATA.readlines.map { |line| line.scan(regexp) }
insults = triplets.select { |t| t.size == 3 }

thousts = [
  'Thoust',
  'Thou',
  'You',

randito

$ time ./perfect_number.rb 8028                                                                                                                                
6
28
496
./perfect_number.rb 8028  0.53s user 0.01s system 99% cpu 0.544 total

This optimized version is *much* better than the original at https://gist.github.com/3961422

randito

$ time ./perfect_number.rb 10000                                                                                                                               
6
28
496
8128
./perfect_number.rb 10000  17.81s user 0.01s system 99% cpu 17.833 total