jbrisbin

import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.StandardSocketOptions;
import java.nio.ByteBuffer;
import java.nio.channels.CancelledKeyException;
import java.nio.channels.ReadableByteChannel;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;

jboner

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

Jud

/*****************************************************************************
 *                QuantCup 1:   Price-Time Matching Engine
 *
 * Submitted by: voyager
 * 
 * Design Overview:
 *   In this implementation, the limit order book is represented using 
 *   a flat linear array (pricePoints), indexed by the numeric price value. 
 *   Each entry in this array corresponds to a specific price point and holds 
 *   an instance of struct pricePoint. This data structure maintains a list 

hintjens

//  The Census Pattern
//  Model 1, over XPUB-XSUB

#include "czmq.h"

static void
counter_task (void *args, zctx_t *ctx, void *pipe)
{
    void *counter = zsocket_new (ctx, ZMQ_XPUB);
    zsocket_set_xpub_verbose (counter, 1);

neomatrix369

Everything I Ever Learned About JVM Performance Tuning @Twitter- by Attila Szegedi

http://www.infoq.com/presentations/JVM-Performance-Tuning-twitter (video & slides)

9 Fallacies of Java Performance - by Ben Evans

http://www.infoq.com/articles/9_Fallacies_Java_Performance (video & slides)

Visualizing Java GC - by Ben Evans

http://www.infoq.com/presentations/Visualizing-Java-GC (video & slides)

Java Garbage Collection Distilled by Martin Thompson

claws

'''
An authentication module for pyzmq modelled on zauth from czmq.

The functions to read and generate certificates should be interoperable
with czmq's zcert's - though are not as fully featured.
'''

import datetime
import glob
import json

NYKevin

CREATE TABLE accounts(
	id serial PRIMARY KEY,
	name VARCHAR(256) NOT NULL
);

CREATE TABLE entries(
	id serial PRIMARY KEY,
	description VARCHAR(1024) NOT NULL,
	amount NUMERIC(20, 2) NOT NULL CHECK (amount > 0.0),
	-- Every entry is a credit to one account...

doctorevil

Crypto Review of Curve25519.java & Crypto.java

By DoctorEvil on Nextcoin.org

Sponsored by MSIN on BitcoinTalk.org

TL;DR

NXT's Crypto.java and Curve25519.java look kosher aside from a signing bug that is currently being worked around.

General Methodology

doctorevil

# a pedagogical implementation of curve25519 with ec-kcdsa
# coded by doctorevil to validate nxt's port of Matthijs van Duin's implementation
# warning: this implementation is not timing attack resistant 
# ec arithmetic equations from http://hyperelliptic.org/EFD/g1p/auto-montgom.html

from hashlib import sha256
from ecdsa.numbertheory import square_root_mod_prime, SquareRootError, inverse_mod

CURVE_P = 2**255 - 19
CURVE_A = 486662

0m15

`/** @jsx React.DOM */`

classSet = React.addons.classSet
ReactCSSTransitionGroup = React.addons.CSSTransitionGroup
ReactTransitionGroup = React.addons.TransitionGroup

CarouselStateMixin = 
	propTypes:
		items: React.PropTypes.array