fluency03

Latency Comparison Numbers
--------------------------
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

fluency03

References from my talk 'Without Resilience, Nothing Else Matters'

• Drift into Failure
• How Complex Systems Fail
• Antifragile: Things That Gain from Disorder
• Leverage Points: Places to Intervene in a System
• Going Solid: A Model of System Dynamics and Consequences for Patient Safety
• Resilience in Complex Adaptive Systems: Operating at the Edge of Failure
• Puppies! Now that I’ve got your attention, Complexity Theory
• [Towards Resilient Architectures: Biology

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#!/usr/bin/env python

#
# Converts any integer into a base [BASE] number. I have chosen 62
# as it is meant to represent the integers using all the alphanumeric
# characters, [no special characters] = {0..9}, {A..Z}, {a..z}
#
# I plan on using this to shorten the representation of possibly long ids,
# a la url shortenters
#

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# Find potential outliers in values array
# and visualize them on a plot

def is_outlier(value, p25, p75):
    """Check if value is an outlier
    """
    lower = p25 - 1.5 * (p75 - p25)
    upper = p75 + 1.5 * (p75 - p25)
    return value <= lower or value >= upper
 

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"""
Results:

multiple_update: 57 ms
copy_and_update: 46 ms
dict_constructor: 56 ms
kwargs_hack: 45 ms
dict_comprehension: 45 ms
concatenate_items: 166 ms
union_items: 163 ms

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{
    "template": "logstash-*",
    "settings" : {
        "number_of_shards" : 1,
        "number_of_replicas" : 0,
        "index" : {
            "query" : { "default_field" : "@message" },
            "store" : { "compress" : { "stored" : true, "tv": true } }
        }
    },

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# Run me with:
#
#     $ nginx -p /path/to/this/file/ -c nginx.conf
#
# All requests are then routed to authenticated user's index, so
#
#    GET http://user:password@localhost:8080/_search?q=*
#
# is rewritten to:
#

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Title

<Additional information about your API call. Try to use verbs that match both request type (fetching vs modifying) and plurality (one vs multiple).>

• URL

  <The URL Structure (path only, no root url)>

• Method:

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JavaScript function hoisting by example

Below are many examples of function hoisting behavior in JavaScript. Ones marked as works successfuly print 'hi!' without errors.

To play around with these examples (recommended) clone them with git and execute them with e.g. node a.js

Notes on hoisting

(I may be using incorrect terms below, please forgive me)

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"use strict";

// `f` is assumed to sporadically fail with `TemporaryNetworkError` instances.
// If one of those happens, we want to retry until it doesn't.
// If `f` fails with something else, then we should re-throw: we don't know how to handle that, and it's a
// sign something went wrong. Since `f` is a good promise-returning function, it only ever fulfills or rejects;
// it has no synchronous behavior (e.g. throwing).
function dontGiveUp(f) {
    return f().then(
        undefined, // pass through success