| #!/bin/bash | |
| # Here short description of this script | |
| # This is just a template to be used for writing new bash scripts | |
| ### | |
| # Based on Google Style Guide: https://google.github.io/styleguide/shell.xml | |
| # General remarks | |
| # * Executables should have no extension (strongly preferred) or a .sh extension. | |
| # * Libraries must have a .sh extension and should not be executable |
This is a proof-of-concept of a couple of concurrent data structures written in Ruby.
The implementations are heavily commented for those interested. There are benchmarks (with results) included below. The results are interesting, but, as always, take with a grain of salt.
AtomicLinkedQueue is a lock-free queue, built on atomic CAS operations.
Changes:
this version includes backport of Greg Price's patch for speedup startup http://bugs.ruby-lang.org/issues/7158 .
ruby-core prefers his way to do thing, so that I abandon cached-lp and sorted-lf patches of mine.
this version integrates 'array as queue' patch, which improves performance when push/shift pattern is heavily used on Array.
This patch is accepted into trunk for Ruby 2.0 and last possible bug is found by Yui Naruse. It is used in production* for a couple of months without issues even with this bug.
| # Nginx+Unicorn best-practices congifuration guide. Heartbleed fixed. | |
| # We use latest stable nginx with fresh **openssl**, **zlib** and **pcre** dependencies. | |
| # Some extra handy modules to use: --with-http_stub_status_module --with-http_gzip_static_module | |
| # | |
| # Deployment structure | |
| # | |
| # SERVER: | |
| # /etc/init.d/nginx (1. nginx) | |
| # /home/app/public_html/app_production/current (Capistrano directory) | |
| # |
| 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 |
| desc "convert a latin1 database with utf8 data into proper utf8" | |
| task :convert_to_utf8 => :environment do | |
| puts Time.now | |
| dryrun = ENV['DOIT'] != '1' | |
| conn = ActiveRecord::Base.connection | |
| if dryrun | |
| def conn.run_sql(sql) | |
| puts(sql) | |
| end | |
| else |
| connection = Faraday::Connection.new('http://example.com') do |builder| | |
| builder.request :url_encoded # for POST/PUT params | |
| builder.adapter :net_http | |
| end | |
| # same as above, short form: | |
| connection = Faraday.new 'http://example.com' | |
| # GET | |
| connection.get '/posts' |
| # unicorn_rails -c /data/github/current/config/unicorn.rb -E production -D | |
| rails_env = ENV['RAILS_ENV'] || 'production' | |
| # 16 workers and 1 master | |
| worker_processes (rails_env == 'production' ? 16 : 4) | |
| # Load rails+github.git into the master before forking workers | |
| # for super-fast worker spawn times | |
| preload_app true |
