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@defunkt
defunkt / gemspec
Created March 9, 2010 01:41
Quickly create a gemspec.
#!/usr/bin/env ruby
# Usage: gemspec [-s] GEMNAME
#
# Prints a basic gemspec for GEMNAME based on your git-config info.
# If -s is passed, saves it as a GEMNAME.gemspec in the current
# directory. Otherwise prints to standard output.
#
# Once you check this gemspec into your project, releasing a new gem
# is dead simple:
#
GC.copy_on_write_friendly = true if GC.respond_to?(:copy_on_write_friendly=)
Benchmark.bm(10) do |x|
x.report do
100.times do
100.times { fork {} }
Process.waitall
end
end
end
class QueryTracer < ActiveSupport::LogSubscriber
ACCEPT = %r{^(app|config|lib)}.freeze
FRAMES = 5
THRESHOLD = 300 # In ms
def sql(event)
return unless event.duration > THRESHOLD
callers = Rails.
backtrace_cleaner.
@mrflip
mrflip / RUNME-demo_of_async_fibers.log
Created April 25, 2011 20:57
A fully-commented demo showing execution flow in the fibers+eventmachine => linear asynchronous code pattern
>> load './RUNME-demo_of_async_fibers.rb'
/Users/flip/ics/backend/son_of_a_batch/RUNME-demo_of_async_fibers.rb:4: warning: already initialized constant FIBER_IDXS
814e5e90 0 f_0 beg main top level
814e5e90 1 f_0 beg em setup this block sets up the eventmachine execution, but no execution-order shenanigans yet
814e5e90 2 f_0 beg fiber stp the end-the-reactor block won't be called for 1.5s, so we get here immediately.
814e5e90 3 f_0 end fiber stp nothing from inside the Fiber.new{} block has run yet.
814e5e90 4 f_0 end fiber stp kick off the fiber...
80d829a0 5 f_1 beg fiber when my_fiber.resume is called, this runs. Now in a new fiber
80d829a0 6 f_1 beg get_result get_result is called from within fiber_1
80d829a0 7 f_1 setup callback set up some code to run 1.5s from now
@croaky
croaky / gist:1089598
Created July 18, 2011 14:01
Transfer data from production to staging on Heroku
heroku addons:add pgbackups --remote staging
heroku addons:add pgbackups --remote production
heroku pgbackups:capture --remote production
heroku pgbackups:restore DATABASE `heroku pgbackups:url --remote production` --remote staging
@tiegz
tiegz / object_profiler.rb
Last active August 29, 2015 14:03
Object Profiler for ruby 2.1.0+
module ObjectSpace
def self.profile(&blk)
require 'objspace'
enable_gc = GC.disable
ObjectSpace.trace_object_allocations(&blk)
objs = Hash.new(0)
ObjectSpace.each_object { |o|
if (file = ObjectSpace.allocation_sourcefile(o)) && (line = ObjectSpace.allocation_sourceline(o))
objs["#{file}:#{line}:#{o.class.name}"] += 1