gtrak

Table of Contents

• 1. Gil Tene - understanding latency workshop
• 2. Gil Tene - Faster Objects and Arrays objectlayout.org
• 3. When worst is best in distributed systems design - Peter Bailis, Stanford
• 4. "All In" with Determinism for Performance and Testing in Distributed Systems - John Hugg, VoltDB
• 5. Caitie McCaffrey - Building Stateful Services - Tech Lead 'observability' at twitter
6. Transactions, myths, surprises and opportunities - Martin Kleppmann

gtrak

(defn remove-nil-vals1
  [m]
  (if-let [s (seq m)]
    (persistent! (reduce-kv (fn [acc k v]
                              (if (nil? v)
                                acc
                                (assoc! acc k v)))
                            (transient (empty m))
                            m))))

gtrak

#!/usr/bin/env boot

(require '[clojure.java.io :as io])

(defn inputs
  [input-dir]
  (->> (io/file input-dir)
       file-seq
       (filter #(.isFile %))))

gtrak

* Mesos for Spark users
  - Ben Hindman, started on mesos 2009
    - berkeley
    - twitter
    - multiple 10k+ machines clusters
  - Mesos
    - 3 Mesos founders now work at Databricks on Spark
    - Constraints/Design-goals
      - static partitioning considered harmful
        - eg. 3 hadoop boxes, 3 spark boxes, etc.

gtrak

    private static class Tuple2<T,U>{
        final T v1;
        final U v2;
        
        Tuple2(T v1, U v2){
            this.v1 = v1;
            this.v2 = v2;
        }
    }
    

gtrak

<gtrak> well, I want just a massive queue that has everything.
<gtrak> then my brain can literally be a reactor loop to the universe.
<arrdem> yeah org mode can do that
<gtrak> including tweets and such.
<arrdem> I wish. lemme know and I'll pitch in on the event stream for life project 'cause it's something I've played with as an idea before
<gtrak> It does seem like a good idea, right?
<gtrak> I also want to write code for prioritization.
<arrdem> it's self defeating, because unless you replace yourself the event stream is incomplete
<gtrak> heuristics and stuch.
<arrdem> which is why I haven't built mine yet.

gtrak

(ns cljs-app.data
  (:require [clojure.string :as string]
            [cljs-app.node-bits :as node]
            [cljs-app.logging :as log]
            [cljs.core.async :as async :refer [<! >!]])
  (:require-macros [cljs.core :refer [specify!]]
                   [cljs-app.macros :refer [when-node]]
                   [cljs.core.async.macros :refer [go go-loop]]))

;; in a macros clj file:

gtrak

(defn parse-string
  [s]
  (h/as-hickory (h/parse s)))

(defn link
  [entry]
  (-> (s/select (s/tag "link")
                entry)
      first
      :attrs

gtrak

(defn upload [data owner]
  (reify
    om/IRender
    (render [this]
      (html [:div {:class "upload"}
             [:form {:enc-type "multipart/form-data"
                     :ref "fileUpload"
                     :role "form"
                     :class "form-inline"}
              [:div {:class "form-group"}

gtrak

(defn upload-form-file [node url method on-success]
  (.send goog.net.XhrIo "/log/upload"
         (fn [e]
           (on-success))
         "POST"
         (new js/FormData node)))


(defn upload [data owner]
  (reify