| require 'openssl' | |
| key = OpenSSL::PKey::RSA.new(2048) | |
| p encrypted_string = key.public_encrypt('my plaintext string', OpenSSL::PKey::RSA::PKCS1_OAEP_PADDING) | |
| p decrypted_string = key.private_decrypt(encrypted_string, OpenSSL::PKey::RSA::PKCS1_OAEP_PADDING) |
| -- show running queries (pre 9.2) | |
| SELECT procpid, age(clock_timestamp(), query_start), usename, current_query | |
| FROM pg_stat_activity | |
| WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' | |
| ORDER BY query_start desc; | |
| -- show running queries (9.2) | |
| SELECT pid, age(clock_timestamp(), query_start), usename, query | |
| FROM pg_stat_activity | |
| WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' |
| class BooleanValue | |
| # https://github.com/rails/rails/blob/master/activerecord/lib/active_record/connection_adapters/column.rb#L8 | |
| FALSE_VALUES = [false, 0, '0', 'f', 'F', 'false', 'FALSE', 'off', 'OFF'] | |
| def self.from_string(value) | |
| Rails.present? ? with_rails(value) : without_rails(value) | |
| end | |
| private |
| # this monit config goes in /etc/monit/conf.d | |
| check process puma_master | |
| with pidfile /data/myapp/current/tmp/puma.pid | |
| start program = "/etc/monit/scripts/puma start" | |
| stop program = "/etc/monit/scripts/puma stop" | |
| group myapp | |
| check process puma_worker_0 | |
| with pidfile /data/myapp/current/tmp/puma_worker_0.pid |
| #!/usr/bin/env ruby | |
| require 'net/telnet' | |
| key_prefix = 'www.your:prefix' | |
| cache_dump_limit = 1000 | |
| localhost = Net::Telnet::new("Host" => "localhost", "Port" => 11211, "Timeout" => 3) | |
| slab_ids = [] | |
| localhost.cmd("String" => "stats items", "Match" => /^END/) do |c| | |
| matches = c.scan(/STAT items:(\d+):/) |
Instrument Fog Requests in Rails
This code adds debug statements to the rails log for each fog reqests (similar to how active record shows SQL queries):
Fog AWS Compute Request (803.0ms) [ {"Action"=>"DescribeInstances", ...} ]
The end of the request includes cumulative Fog info:
Completed 200 OK in 6043ms (Views: 2955.0ms | ActiveRecord: 319.9ms | Fog: 1642.6ms, 4 reqs)
My largest Sidekiq application had a memory leak and I was able to find and fix it in just few hours spent on analyzing Ruby's heap. In this post I'll show my profiling setup.
As you might know Ruby 2.1 introduced a few great changes to ObjectSpace, so now it's much easier to find a line of code that is allocating too many objects. Here is great post explaining how it's working.
I was too lazy to set up some seeding and run it locally, so I checked that test suite passes when profiling is enabled and pushed debugging to production. Production environment also suited me better since my jobs data can't be fully random generated.
So, in order to profile your worker, add this to your Sidekiq configuration:
if ENV["PROFILE"]
| MAX_DISTANCE_AWAY_IN_KM = 100.0 | |
| RAD_PER_DEG = 0.017453293 | |
| Rmiles = 3956 # radius of the great circle in miles | |
| Rkm = 6371 # radius in kilometers, some algorithms use 6367 | |
| Rfeet = Rmiles * 5282 # radius in feet | |
| Rmeters = Rkm * 1000 # radius in meters | |
| def haversine_distance( lat1, lon1, lat2, lon2 ) | |
| dlon = lon2 - lon1 |