Christos Zisopoulos christos

Tips for optimizing performance of the Discourse gigantic test suite

Change memory allocator

default:            9:37
tcmalloc:           8:32
lockless:           8:19
jemalloc 3.6.0: 7:45

Problem-Solving Games

My daughter and I love playing problem-solving/adventure games together. Here's a record of them.

Finding a Ruby memory leak using a time analysis

When developing a program in Ruby, you may sometimes encounter a memory leak. For a while now, Ruby has a facility to gather information about what objects are laying around: ObjectSpace.

There are several approaches one can take to debug a leak. This discusses a time-based approach, where a full memory dump is generated every, say, 5 minutes, during a time that the memory leak is showing up. Afterwards, one can look at all the objects, and find out which ones are staying around, causing the

Finding a Ruby memory leak using a time analysis

When developing a program in Ruby, you may sometimes encounter a memory leak. For a while now, Ruby has a facility to gather information about what objects are laying around: ObjectSpace.

There are several approaches one can take to debug a leak. This discusses a time-based approach, where a full memory dump is generated every, say, 5 minutes, during a time that the memory leak is showing up. Afterwards, one can look at all the objects, and find out which ones are staying around, causing the

Colorful (2010) [T]

Probably not the title that most people expected to see in the #1 slot. I urge everyone to give it a shot though. No other film has ever brought me through a greater spectrum of emotions. It's a supernatural film, but the characters are so well fleshed out and developed that they feel real. I've probably seen a hundred films since, but none have compared.
Time of Eve (2010) [T]

Director: Yasuhiro Yoshiura - "Sometime in future Japan, androids have been involved in every aspect of peoples lives. One day, upon checking his android's behavioral log, Rikuo, a student, noticed his android's returning times have been odd recently. With his friend Masaki, they found out the place where his android, Sammy, have been visiting: a small cafe called Eve no Jikan where an

Rails multi-database pattern

The parent class for models that are persisted on a different database app/models/public_database_model.rb:

# Public: Provide a base class for accessing the public database.
# All models inheriting from this class will use by default the data store DB.
class PublicDatabaseModel < ActiveRecord::Base

Tell Active Record (AR) to not look up for a table called like this class,

This list is based on aliases_spec.rb.

You can see also Module: RSpec::Matchers API.

matcher	aliased to	description
a_truthy_value	be_truthy	a truthy value
a_falsey_value	be_falsey	a falsey value
be_falsy	be_falsey	be falsy
a_falsy_value	be_falsey	a falsy value

	default: &default
	adapter: mysql2
	encoding: utf8mb4
	username: root
	password:
	host: localhost
	variables:
	sql_mode: TRADITIONAL,NO_AUTO_VALUE_ON_ZERO,ONLY_FULL_GROUP_BY

	development:

	# You don't need Fog in Ruby or some other library to upload to S3 -- shell works perfectly fine
	# This is how I upload my new Sol Trader builds (http://soltrader.net)
	# Based on a modified script from here: http://tmont.com/blargh/2014/1/uploading-to-s3-in-bash

	S3KEY="my aws key"
	S3SECRET="my aws secret" # pass these in

	function putS3
	{
	path=$1

	# Usage:
	#
	# ruby irpf.rb tax_base
	#
	# Example:
	#
	# ruby irpf.rb 65300
	# 65300 €, 22722 €, 34.8%
	#
	# Where 22,722 € is the IRPF to pay, and 34.8% is the real rate, that is,