strong_silent_t

By name servers they mean DNS. I don't believe it is used and I hadn't heard of it, more info here if you search WKS: https://en.wikipedia.org/wiki/List_of_DNS_record_types

Others have answered, but I think the general principle for a Region is that between the AZs you have less than 1ms latency, physical separation between the data centers, but they may still be in the same floodplain, be able to be hit by the same hurricane, etc.

More info here if you want to see how regions are structured at a high level of detail: https://youtu.be/AyOAjFNPAbA?t=15m21s

Not sure, I haven't used that platform personally, there is probably a debugging interface to the chip but it will probably require different hardware/software.

This is similar to what I did: https://learn.adafruit.com/proper-step-debugging-atsamd21-ar... . That is for that specific platform, not sure if there is something similar for the other versions.

I used the J-Link but I wanted to do it on Linux, so I used the JLink GDB Server along with the GDB build that comes with the Arduino IDE. It probably takes me a good 5 minutes to get everything set up, but the basic stuff works: breakpoints, stack trace, reading and writing memory locations.

The setup is a little convoluted, I'm not sure if there is a better way, but here are my notes:

    Procedure for running w/ debugger attached.
    
    1. disconnect debugger's usb
    2. connect device via usb
    3. arduino IDE program device
    4. identify elf, set up gdb with elf.
    5. plug in debugger
    6. run jlink gdb server
    7. attach gdb to jlink server "target remote:2331"
    8. "monitor reset", "continue" to re-run target from beginning.
    9. observe device is recognized by Arduino IDE
    10. open Arduino IDE serial monitor to interact with device.
    
    Now, Ctrl+C in GDB halts device, and stack etc. can be inspected, and
    then it can continue running with "cont".
    
    To rerun the device with the same program without redoing everything,
    go to step 8 and reset the device. and continue from there.
    
    To find .elf on linux:
    ==================================================
    find /tmp -name sketch_name.ino.elf 2>/dev/null
    

    gdb location:
    ==================================================
    /home/user/.arduino15/packages/arduino/tools/arm-none-eabi-gcc/4.8.3-2014q1/bin/arm-none-eabi-gdb
    
    
    JLink setup command:
    ==================================================
    JLinkGDBServer -device ATSAMD21G18A -if SWD -speed 4000
    

    gdb attachment:
    ==================================================
    (gdb) target remote:2331

I find it depends a lot on my level of understanding of the project I'm working on. If I wrote 20% or more of the code, or if I was involved in the design, etc., when there is a problem I know just where to look and can get there quickly.

For example, if I'm working on a Python script under 1000 lines I would never use a debugger. I might use wireshark or linux system tools if something was really wrong, but usually the trackback or program output is sufficient.

I've also tried to debug an Arduino project where I had a lot less knowledge of how the system works, and if I wasn't able to attach a debugger I don't want to know how long it would have taken me to find the problem (calling a null function pointer causes an interrupt that didn't have any handler).

I've also tried to debug other people's projects in high level languages, without a debugger where after taking about an hour to figure it out based on pure reason, realizing it would have been very quick and easy to find with a debugger.

I think if you look at what a program is doing, and at that point you can't form a testable hypothesis as to what is happening, at that point a debugger will certainly be faster if you know how to use it.

I think if the government is going to subsidize something, politically aerospace makes a lot of sense. It has jobs for engineering, technicians, and high-skill trades. It has a long planning horizon and lots of regulation (meaning less short term competitive forces at play). It has defense applications. The downside is that everyone else is also subsidizing it, so it is still hard to compete.

Every zero-sum adversarial system would be a lot more efficient if they accepted the judgement of a third party instead. How much energy could we save if we dismantled the court system, elections, and pro sports?

I think DAG coins could be a lot more efficient, but I'm not totally solid intellectually on how they achieve consensus on conflicting spends so I'm not sure it will work as a general solution. The only one I've used, nano, has I believe no mining reward, and I think consensus is achieved based on a voting process weighted by proof-of-stake among online nodes -- the incentive for participating in the system is that the system has value for you in other ways. I'm not closely following ETH PoS research, but it will be interesting to see what they can accomplish, it could create a huge reduction in energy consumption.

I'd be really interested if anyone has a book or similar on supply and demand curves estimation by experiment. Ideally I'm looking for a cookbook type book less so than a theory book.

If you're referring to financial markets, I personally learned a lot from Trading and Exchanges: Market Microstructure for Practitioners, although I didn't finish it. But it explains the basic characteristics of financial markets, and why they are set up the way they are. It isn't necessarily going to be obvious and financial markets are based on hundreds of years of accumulated knowledge.

Ok, I doubt I'll ever take an hour to listen to this, but I really enjoyed the book. It was very interesting to see the little particularities of the legal system and the participants that had a big impact. I basically read it straight through in one shot as the host said he did as well. I found the writing to be florid at times (there was a seamless segue between an anecdote of Julius Caesar crossing the Rubicon and Hulk Hogan's decision to sue against the distribution of the hidden camera sextape that made me actually laugh out loud) but I found the asides were unobtrusive enough that it didn't affect the reading.

I like the book Information Rules by Shapiro and Varian as a review of these kinds of concepts in general. I don't think it is necessary to even view these topics as strategy, to a certain extent it is just the nature of the incentives and there will be a tendency for things to work out along these lines. Here is a snapshot of the table of contents, from this it should be pretty clear if it is interesting to you: https://imgur.com/a/2yU6OpA

Thanks, not OP but that looks useful to me. For context, I've used the strategy in OP to debug a small linux system running on an SD card, if I have one version that has a bug and one that doesn't, and I don't know the difference, I can image them both, mount them and diff the whole system (i.e. with meld.) And it can be done with the same card over time. I'd like to figure out how to do this with VM disks as well but I've never had a pressing need.

I like the way Ben Horowitz puts it in his good pm, bad pm document:

Good product managers focus the team on revenue and customers. Bad product managers focus team on how many features Microsoft is building. Good product managers define good products that can be executed with a strong effort. Bad product managers define good products that can’t be executed or let engineering build whatever they want (i.e. solve the hardest problem).

As an engineer, I want to find the demons that are out there in the problem space and assault them, I want to eliminate all weakness from my precious software. But from the business POV I know we need to provide value to customers quickly and efficiently with the available resources, which is usually not the same thing.

For typing I doubt it, ideally you should be able to type fine if the display only updated every 10 seconds.

For i.e. the arrow keys, or anything interactive you will probably have to be watching for the response.

I think it is a very reasonable test. There are other industries that regulate themselves in other ways. For example, a huge training process and then jail time for lying about it, for doctors or lawyers. Or other ways to eliminate the risk like hiring as contractors for specific jobs, or comission based payment.

For a senior role:

1. Someone who can't write and debug a for-loop and an if-statement isn't going to be able to provide training and support to junior level hires. At all.

2. Making high-level changes and performance improvement both require good process discipline, and the ability to write a lot of code to actually accomplish it.

I think there are high value software management tactics that can be implemented without knowing how to code, for example, change control, or enforcing limits on work in progress via. kanban, but for a role that has either "software" or "developer" I think fizzbuzz is a very low bar.

I personally like binary search as in interview question. The basic principle is simple, but there are enough edge cases and variations to make it interesting.

It does look like a really interesting avenue of research. I see a lot of statistical "evidence" presented as justifying interventions without even hesitating to consider if they've got it the wrong way around in terms of causality.

It seems it will be focused on large scale products out of necessity because of the availability of structured data and public disclosure.

There is one preliminary paper linked in the article, which I haven't read: https://dl.acm.org/citation.cfm?id=3172876

It is really interesting to see ways to establish causality without a randomized controlled trial, since in a lot of circumstances an RCT is impossible or unethical, and because for many decision making purposes you need to evaluate interventions, not just relationships.

2-way personalized search. You search Google and Google searches you.

I hadn't heard 50/50 in that context before, it is a gunshot to the spine?

This may be what you're looking for: https://github.com/owid/owid-grapher

In particular I think China will have a problem with this: https://data.worldbank.org/indicator/NE.CON.PETC.ZS?end=2016...

(included some other countries to compare, Saudi Arabia is also an interesting one but it messes up the graph.)

I think the ideal scenario for this tech is running a downtown core to airport shuttle:

- a short trip allows battery needs to not be excessive

- bypass traffic, you don't have to go all that fast to get a huge speedup, and remove the extra buffer time on traffic uncertainty

- radically less infrastructure than roads or rails, reduces the cost of adding more pickup zones

In cites with poor airport to downtown infrastructure you could probably start off as a high-end service and charge i.e. 5x than an airport limo.

A few early thoughts:

I think about half of their 2017 net loss was due to something to do with Convertible Notes, that they're explaining on pages F-43 and F-44.

I'm trying to calculate patio11's "fundamental equation of SAAS" ( https://twitter.com/patio11/status/965985835790184448 ) for the numbers for churn, subscribers, and ARPU on pages 67 to 70ish. Will update if I actually figure it out.

Ok, here is my attempt for their premium service:

pp68, 2017 ARPU = 5.32 EUR/mo.

pp69, 2017 Churn = 5.5%/mo.

pp79, 2017 Customer Acquisition, 48 Million at end of 2016, 71 Million at end of 2017. (71 - 48) / 48 * 100% = 48%. To convert to monthly, if I just divide by 12 it is 4%/month. If I do (1.48)^(1/12) it is 3.3%. I guess this is net of churn, So their fresh acquisition I would estimate at 5.5% + 3.3% = 8.8%.

I'll leave the math as an exercise to the reader, partly because I don't know what is being summed over in the formula.

I'd be curious to know at what number of users do they break-even if their cost of revenue, sales, and marketing are linear to users and their other non-financial costs remain fixed.

In that sense, it might actually be "safer" for an individual American to use a Chinese phone. It may be backdoored, but at least the PLA isn't going to share your vacation pics with the DEA, but the NSA might.

Everytime this question comes up I am powerless to resist re-implementing it.

http://codepad.org/KKut69jV

  #include <stdio.h>
  
  int main() {
    int i;
    for (i = 1; i < 101; i++) {
  
      int div3 = 0 == i % 3;
      int div5 = 0 == i % 5;
  
      if (div3 || div5) {
        printf("%s%s\n", 
          div3 ? "fizz" : "", 
          div5 ? "buzz" : "");
      } else {
        printf("%d\n", i);
      }
    }
    return 0;
  }

I will admit, it took me 4 tries to get this to compile.

Would you recommend a book on the planning?

As a tech-bro type person I'm not enjoying our daily two minutes of hate from ivy league and oxbridge types against our various failures of moral purity. But there is a lot of value in this type of piece for i.e. a 22-year old female fresh grad entering this environment to cast aside euphemisms and frippery and explain in real basic detail exactly who is getting fucked by whom, and what the terms are and are not.

"Extreme Ownership" was popular this year: https://www.amazon.com/Extreme-Ownership-U-S-Navy-SEALs/dp/1...

My personal favourite is called /Winning Through Intimidation/ , I think it is much more relevant to our capitalistic and legalistic society than military memoirs or the ancients, as much as I enjoy them. https://www.amazon.com/Winning-through-Intimidation-Victor-B... . It is not prescriptive because it is a bit dated and specific to real estate, but the core ideas are rock solid.

Annoyed to see a unit error in the first paragraph.

Bulgaria nominal GDP is $50 billion PER YEAR.

Two Sigma assets under management is $50 billion. (Not per year).

If your car goes 100km/hour, and Shelbyville is 100km away, your car is not the distance of Shelbyville.

So, if I'm understanding right, it is using the database server instances as the current Aurora does. You just aren't responsible for managing them, the service makes those decisions within the spectrum of Aurora's capabilities and can change it in a very small time increment.

EDIT: pretty impressive though, looking at James Hamilton's criteria for "Automatic Management and Provisioning" here: https://www.usenix.org/legacy/event/lisa07/tech/full_papers/... , I think this addresses everything database related, as long as you are under the maximum capacity of Aurora.

So for me, the most realistic price drop scenario is something that creates a big increase in supply and decrease in demand at the same time. For MtGox you have a crisis that lowers trust in brokers, decreasing demand, and huge hoard of stolen coins going to a criminal that wants to profit, increasing supply. Holders who bought bitcoin for a reason will sell for a reason, and they're heavily incentivized not to do a panic selloff, unless they think bitcoin is dying.

I agree bitcoin is inadequate as a currency. (I think ETH is better as a currency, since it sort of has the "tax base" of executing contracts and enshrining the results on the blockchain.) I view it as a store of value. If your wealth is mostly represented as various numbers in various databases (mine is,) then bitcoin is a robust form of integer storage, or at least vulnerable in ways that are uncorrelated with my other wealth storage providers.

I think there are two main drivers of price increase in 2018:

- me-too buyers drawn by the huge 2017 increases

- investors that have a mandate to seek out high-risk investments for a certain %age of their portfolio, and are gradually overcoming technical and regulatory barriers ( https://www.bloomberg.com/news/articles/2017-11-16/bitcoin-e... )

For a decrease

- MtGox style failure of a company holding a lot of coins

- crypto-diversification as other projects get stronger