shoover

(defun my-indent-line ()
  "Make single-semicolon lisp comments indent like ;;-comments.
Mostly cribbed from `lisp-indent-line'."
  (interactive)
  (let ((indent (calculate-lisp-indent)) shift-amt end
        (beg (progn (beginning-of-line) (point))))
    (skip-chars-forward " \t")
    (if (or (looking-at "\\s<\\s<") (not (looking-at "\\s<")))
        (lisp-indent-line)
      (if (listp indent) (setq indent (car indent)))

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

hellerbarde

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

zerokarmaleft

AA = Rickard Stark (M)        AB = Eddard Stark (M)         AC = Catelyn Tully (F)
AD = Brandon Stark (M)        AE = Benjen Stark (M)         AF = Jon Snow (M)
AG = Robb Stark (M)           AH = Sansa Stark (F)          AI = Arya Stark (F)
AJ = Bran Stark (M)           AK = Rickon Stark (M)         AL = Hoster Tully (M)
AM = Minisa Whent (F)         AN = Edmure Tully (M)         AO = Lysa Tully (F)
AP = Jon Arryn (M)            AQ = Robert Arryn (M)         AR = Tytos Lannister (M)
AS = Tywin Lannister (M)      AT = Joanna Lannister (F)     AU = Kevan Lannister (M)
AV = Cersei Lannister (F)     AW = Jamie Lannister (M)      AX = Tyrion Lannister (M)
AY = Robert Baratheon (M)     AZ = Joffrey Baratheon (M)    BA = Myrcella Baratheon (F)
BB = Tommen Baratheon (M)     BC = Lancel Lannister (M)     BD = Steffon Baratheon (M)

balupton

Debugging & Profiling Node.js - Moved! Click here to be redirected to the new location.

clj_drone.clj

(ns clj-drone.core
  (:import (java.net DatagramPacket DatagramSocket InetAddress)))

(def drone-host (InetAddress/getByName "192.168.1.1"))
(def at-port 5556)

(def socket (DatagramSocket. ))

(defn send-command [data]
  (.send socket

pbailis

A friend asked me for a few pointers to interesting, mostly recent papers on data warehousing and "big data" database systems, with an eye towards real-world deployments. I figured I'd share the list. It's biased and rather incomplete but maybe of interest to someone. While many are obvious choices (I've omitted several, like MapReduce), I think there are a few underappreciated gems.

###Dataflow Engines:

Dryad--general-purpose distributed parallel dataflow engine
http://research.microsoft.com/en-us/projects/dryad/eurosys07.pdf

Spark--in memory dataflow
http://www.cs.berkeley.edu/~matei/papers/2012/nsdi_spark.pdf

whoahbot

Clojure West

Domain driven design with Clojure

• Organizing larger applications
• Domain logic shouldn’t include handlers for bad/unclean data.
  • validateur, bouncer, clj-schema for checking data going into the pipeline.
  • domain-specific, semantic checks
  • TODO: Any better ways for doing this conditional validation.
  • Need to factor out common data cleaning utils into shared library.

nn.clj

(ns martha.core
  (:require [clojurewerkz.titanium.graph    :as g]
            [clojurewerkz.titanium.vertices :as v]
            [clojurewerkz.titanium.edges    :as e]
            [clojurewerkz.titanium.types    :as t]
            [ogre.core                      :as q]))

(def conf {:storage {:backend "embeddedcassandra"
                     :hostname "127.0.0.1"
                     :keyspace "martha"

aphyr

aphyr@node4:~/riak/rel/riak$ sudo strace -p 1977
Process 1977 attached - interrupt to quit
select(8, [6 7], NULL, NULL, {0, 1370}) = 0 (Timeout)
select(8, [6 7], NULL, NULL, {0, 10000}) = 0 (Timeout)
select(8, [6 7], NULL, NULL, {0, 10000}) = 0 (Timeout)
select(8, [6 7], NULL, NULL, {0, 10000}) = 0 (Timeout)
select(8, [6 7], NULL, NULL, {0, 10000}) = 0 (Timeout)
select(8, [6 7], NULL, NULL, {0, 10000}) = 0 (Timeout)
select(8, [6 7], NULL, NULL, {0, 10000}) = 0 (Timeout)
select(8, [6 7], NULL, NULL, {0, 10000}) = 0 (Timeout)