djspiewak

Quick Tips for Fast Code on the JVM

I was talking to a coworker recently about general techniques that almost always form the core of any effort to write very fast, down-to-the-metal hot path code on the JVM, and they pointed out that there really isn't a particularly good place to go for this information. It occurred to me that, really, I had more or less picked up all of it by word of mouth and experience, and there just aren't any good reference sources on the topic. So… here's my word of mouth.

This is by no means a comprehensive gist. It's also important to understand that the techniques that I outline in here are not 100% absolute either. Performance on the JVM is an incredibly complicated subject, and while there are rules that almost always hold true, the "almost" remains very salient. Also, for many or even most applications, there will be other techniques that I'm not mentioning which will have a greater impact. JMH, Java Flight Recorder, and a good profiler are your very best friend! Mea

FranklinYu

links for old versions of Docker for Mac

Deprecated

Docker provides download links in release note. They promised that

(we) will also include download links in release notes for future releases.

Note:

alexcrichton

extern crate env_logger;
extern crate futures;
extern crate tokio_core;
extern crate net2;
extern crate num_cpus;

use std::env;
use std::io;
use std::net::SocketAddr;
use std::thread;

bitwalker

defmodule Config do
  @moduledoc """
  This module handles fetching values from the config with some additional niceties
  """

  @doc """
  Fetches a value from the config, or from the environment if {:system, "VAR"}
  is provided.

  An optional default value can be provided if desired.

zedar

Apache Hadoop - add native libraries

If native libraries are not available the following message is displayed with every hadoop command: hadoop checknative

WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable

• Clone hadoop source code

omnibs

Comparative Benchmark Numbers @ Rackspace

I've taken the benchmarks from Matthew Rothenberg's phoenix-showdown, updated Phoenix to 0.13.1 and ran the tests on the most powerful machines available at Rackspace.

Results

Framework	Throughput (req/s)	Latency (ms)	Consistency (σ ms)

ianblenke

Allow routing allocations:

curl -XPUT localhost:9200/_cluster/settings -d '{
                "transient" : {
                    "cluster.routing.allocation.enable" : "all"
                }
        }'

indragiek

public struct RandomNumberGenerator: SequenceType {
    let range: Range<Int>
    let count: Int
    
    public init(range: Range<Int>, count: Int) {
        self.range = range
        self.count = count
    }
    
    public func generate() -> GeneratorOf<Int> {

jashkenas

#!/usr/bin/env coffee

fs = require 'fs'
sh = require 'execSync'

config = JSON.parse fs.readFileSync 'package.json'

fs.renameSync 'package.json', 'package.json.real'

name = config.name = "#{config.name}-semver"

higepon

//
//  API.swift
//
//  Created by Taro Minowa on 6/10/14.
//  Copyright (c) 2014 Higepon Taro Minowa. All rights reserved.
//

import Foundation

typealias JSONDictionary = Dictionary<String, AnyObject>