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Colin McMillen
Works at Google
Attended Carnegie Mellon University
Lives in Boston
9,599 followers|1,999,503 views
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429 people
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9,599 people
Work
Occupation
Software Engineer
Employment
  • Google
    Senior Software Engineer, 2009 - present
  • reCAPTCHA
    Co-Founder, 2007 - 2009
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Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Currently
Boston
Previously
Minneapolis - Pittsburgh - Tokyo
Story
Bragging rights
I proposed to my wife using obfuscated Perl code. My Erdős number is 4.
Education
  • Carnegie Mellon University
    Ph.D. Computer Science, 2003 - 2009
  • University of Minnesota
    B.S. Computer Science, 1999 - 2003
  • Robbinsdale Cooper High School
    1995 - 1999
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Colin McMillen

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Monday: 75 and sunny. This morning: 34 and "ice pellets".
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Mother Nature is quietly snickering in the background.  "You think you're smart, huh?  I've still got a few tricks up my sleeve!"
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Colin McMillen

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Colin McMillen

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A coworker gave me permission to reshare this to the public.

The Microarchitecture of Crochet

The Crochet processor presents a simple yet intriguing model of computation. At heart, a hardware implementation of Crochet centers around a single functional unit (called the "hook") whose sole primitive operation consists of drawing a single bit of data (stored as a loop of yarn) through the space enclosed by an existing loop. 

This simple operation (denoted "CH") is variously compounded to form a more expressive instruction set consisting of such operations as SC, HDC, DC, TC, and a variety of directional slip-stitch instructions. The hook acts as a kind of accumulator, in that all instructions implicitly act on the hook. A typical Crochet computation is bootstrapped from a single pre-computed loop loaded onto the hook at startup time by the operator.

The Crochet memory model is analogous to a Turing machine's tape, save that instead of being a single unbounded row it is organized into a grid or cylindrical configuration (depending upon implementation) with an unbounded number of rows. The units of storage are called "stitches" instead of "cells", however, and with a few notable exceptions (see below) the hook only ever advances away from the origin.

Although the Crochet processor may read any previously-written location (at a lookup cost proportional to the row distance and offset back from the PC), writes may generally occur only at the PC—i.e., the hook's current location. Some implementations support special instructions (e.g., FPxC and BPxC) that may write values explicitly tied to stitches in previous rows, but these are uncommon in most workloads. And, in any case, it is not possible to write to any given cell without first writing values to some constant fraction of all the cells closer to the origin, typically in some regular pattern. While it is possible to re-write arbitrary earlier cells, most implementations find this annoying to do, since it requires that all the subsequent stitches be recomputed. 

The Crochet processor is equipped with a finite but unbounded reservoir of input loops (called the "skein") and is equivalent in expressive power to a linear-bounded automaton. However, in practice the expressiveness of the ISA—as well as the quality of its output—depends greatly upon the specific implementation of the processor, and  how good the processor's control unit is at keeping track of details.
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As a crocheter with a degree in computer science, I approve this message. :-) 
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Colin McMillen

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#BEES  
 
Thanks to +failblog, I think we have identified the cause of print media decline.
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Beads?
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Colin McMillen

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One thing I like about knowing a lot of Eve players is that if they ask how I'm doing, I can say "triage green", and they know what I mean.
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Bertha Tang's profile photoPhilip Kovac's profile photoReuven Lazarus's profile photoMatthew Brewer's profile photo
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I understood that. I don't play eve, but I have medical training.
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Colin McMillen

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#pixelpushing

And then it was April 8th, the day when Microsoft officially ended support and updates for Windows XP, and if you were to ask me if I still had a machine somewhere in my basement running that lovely OS, I'd be all like...
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This gif is perfect in so many ways.
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In their circles
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Colin McMillen

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Excellent:

The Pulitzer Prize for public service was awarded today to the NSA revelations reported jointly by the Guardian U.S. and the Washington Post, including work from journalists Glenn Greenwald, Laura Poitras, Barton Gellman, and Ewan MacAskill, based on the leaked documents provided by Edward Snowden. The Guardian was recognized for "helping through aggressive reporting to spark a debate about the relationship between the government and the public over issues of security and privacy," while the Post was credited with "authoritative and insightful reports that helped the public understand how the disclosures fit into the larger framework of national security."
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Colin McMillen

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Hey Boston-area folks! If you're interested in helping Google make better products, you can apply to be in a focus group conducted at the Cambridge office.  

If you're interested, fill out the following form:
https://docs.google.com/forms/d/1JEbGqkPZUEkcqqQrDtxbEE_jWnPkWDe47GtzPYQWOVk/viewform?usp=send_form
and someone will get back to you if you're selected for the study. 
Drive
Participate In a Google study at the Cambridge Offices!Hello, I am contacting you with a short survey to verify your eligibility for an upcoming study with Google. This study will help the Google team better understand your needs in order to incorporate them into future product enhancements. If you are interested in participating, please complete the questionnaire linked below. We’ll then be in touch directly to discuss details and set your appointment time if you are selected to participate. **Pl...
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Colin McMillen

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Beautiful abstract art?

Rather this is a graphical representation of the frequency of four digit PIN codes. On the x-axes we have the first two PIN digits from 00.. to 99.., on the y-axes we have the last two digits from ..00 to ..99. Popular PIN codes include the yellow diagonal, PIN codes of the form XYXY, and even more bright XXXX. The vertical yellow line are PIN codes marking a year, mostly between the years 1930-2010. The yellow blob on the lower left are US formatted calendar days from 01/01 to 12/31 (you can even see how many days each month has). Also singleton yellow dots can be explained.

Anyway, it is beautiful, in my opinion.
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See, my take-away from the top-20 PIN list was that 1 in every 200 people is an idiot, and also twelve. ("6969", chosen by 0.512%) This is probably an underestimate.
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Colin McMillen

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A: LITERALLY NOTHING
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Spock and Kirk clearly have misplaced their hats.
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