anyone know what framework they used to do visualizations?
How We Built r/Place
191–200 of 255 posts
Re: How We Built r/Place
#192I love write-ups like this because they are such a nice contrast to the too-common comments on Reddit and HN where people claim that they could rebuild FB or Uber as a side project. Something as superficially trivial as the r/Place requires a tremendous amount of effort to run smoothly and there are countless gotchas and issues that you'd never even begin to consider unless you really tried to implement it yourself.…
> the too-common comments on Reddit and HN where people claim that they could rebuild FB or Uber as a side project. I do and don't agree with you. Whats really going on here is that development time scales linearly with the number of decisions you need to make. Decisions can take the form of a product questions - "what are we making?" and development questions - "how should we implement that?". There are three reason…
First off, it's a bit unfair to me that you were the one to make this comment, since your very extensive experience and deep knowledge of real-time systems makes you uniquely qualified to disprove my point!! hehe
But in all seriousness, I agree with most of what you said - I think I'm just more bearish on people's ability to infer those many decision points without being given the blueprint like we were in this article.
If you are a senior engineer at FB and you decide to make Twitter in your spare time, I buy that lots of experience and knowledge gained at your job can probably get you going fairly quickly. But I have never seen an example of engineers discussing sophisticated systems like these where crucial aspects of its success in terms of implementation didn't rely on some very specific knowledge/study of the particular problem being solved that could only be gleaned after trying things out or studying it very carefully. The representation of the pixels is a great example in this case -- they go into wonderful detail about why they decided to represent it the way they did, which in turn informs and impacts how the rest of the stack looks like.
I think at one point Firebase had it as one of their example apps something which very closely mirrored what they did with r/Place, so I agree that one could probably build some "roughly" like it somewhat quickly. I agree that in general knowledgeable individuals could probably grok things which would in some form resemble popular services we know today. The devil is in the "roughly," though. I think that often what makes them be THE giant services we know are things that let them have the scale which very few of us have ever needed or know how to deal with, or because they have combined tons of "below the water" features and polish like you mentioned. When really basically most web apps that we use are CRUD apps which we all know how to build, I think maybe we need to give more weight to these "below the water" features in terms of how much they actually contribute to the success of the applications we use.
Re: How We Built r/Place
#193Why use Redis and multiple machines instead of keeping it in RAM on a single machine? I'm not claiming the Reddit people did anything wrong; they have a lot more experience than me here obviously. I'm just trying to figure out why they couldn't do something simpler. 333 updates/sec to a 500kB packed array, coupled with cooldown logic, should have a negligible performance cost and can easily be done on a single thread…
Updating a bitmap 333 times a second is trivial with one core. Handling 100K websocket connections is the tricky bit I think!
And there's only half a meg of data! Serving the readers is a much more interesting problem than managing the writes, and tbh I'd just keep a rolling "pixels that have changed in the last 10 seconds" diff going, pushed out every 100ms, compressed and cached, and have clients poll for it. Easy peasy, websockets just complicate life.
Re: How We Built r/Place
#194Earlier quoted context omitted.
> the too-common comments on Reddit and HN where people claim that they could rebuild FB or Uber as a side project. I do and don't agree with you. Whats really going on here is that development time scales linearly with the number of decisions you need to make. Decisions can take the form of a product questions - "what are we making?" and development questions - "how should we implement that?". There are three reason…
I wish I had enough spare cash to take you up on a bet that you could implement this in less than a weekend. Maybe HN can crowdfund paying you for two days at $1000/day to replicate, versus your time and a $3000 rebate if you can't.
My loved ones are out of town, so you're on! I'll do it for the fun of it and the experience. And because I still haven't built anything on top of kafka, but there's no time like now to fix that.
The challenge is: Meet the main requirements of r/place: 1000x1000 image, a web based editor, 333+ edits / second, with an architecture that can scale to 100k simultaneous users (although that part will be hard to actually test). I won't implement mobile support or notifications, and I won't implement any sort of user access control (thats out of scope). The challenge is to do it & get it hosted online before I go to bed on Saturday (so, I'm allowing myself some slop there). But its already 1:30pm on Friday, so I think that easily qualifies as "less than a weekend".
As a stretch I'm going to write all the actual code in nodejs while aiming for well into the thousands / tens of thousands of writes per second territory.
I'm willing to accept some fun stakes if anyone wants to propose them (ice bucket challenge level stuff). I'll live-tweet progress here - https://twitter.com/josephgentle
(Edit: fixed days)
Re: How We Built r/Place
#195Our initial approach was to store the full board in a single row in Cassandra and each request for the full board would read that entire row. This is the epitome of an anti-pattern .I sincerely hope that this approach was floated by somebody who had never used Cassandra before. Even if individual requests were reasonably fast, you are sticking all of your data in a single partition, creating the hottest of hot spots…
They're using (timestamp, user) as their compound key, which would partition rows by timestamp, no?
Re: How We Built r/Place
#196Earlier quoted context omitted.
I wish I had enough spare cash to take you up on a bet that you could implement this in less than a weekend. Maybe HN can crowdfund paying you for two days at $1000/day to replicate, versus your time and a $3000 rebate if you can't.
My loved ones are out of town, so you're on! I'll do it for the fun of it and the experience. And because I still haven't built anything on top of kafka, but there's no time like now to fix that. The challenge is: Meet the main requirements of r/place: 1000x1000 image, a web based editor, 333+ edits / second, with an architecture that can scale to 100k simultaneous users (although that part will be hard to actually t…
Wait... Where are you that it's Saturday already?
I thought I knew timezones... But that's 40+ hours ahead of me.
Re: How We Built r/Place
#197Now I'm curious, Are there any websites that do something similar to /r/place? (hackathon idea?) Also, reminds be of the million dollar front page [1]. [1] https://en.wikipedia.org/wiki/The_Million_Dollar_Homepage
4chan's moot's previous startup was something called canvas.
Re: How We Built r/Place
#198Earlier quoted context omitted.
My loved ones are out of town, so you're on! I'll do it for the fun of it and the experience. And because I still haven't built anything on top of kafka, but there's no time like now to fix that. The challenge is: Meet the main requirements of r/place: 1000x1000 image, a web based editor, 333+ edits / second, with an architecture that can scale to 100k simultaneous users (although that part will be hard to actually t…
Wait... Where are you that it's Saturday already? I thought I knew timezones... But that's 40+ hours ahead of me.
Errr... oh, that thing is happening where its a public holiday so I'm a bit unmoored from reality. I'll get it done by Saturday night, not Sunday night.
Re: How We Built r/Place
#199Given the scale described, it sounds like they could have had a single machine that held the data in memory and periodically flushed to disk/DB to support failing over to a standby.
You're basically describing how we used redis for this project.
I suppose so, but then what did you gain from the extra hop to redis?
Re: How We Built r/Place
#200Good article. One security issue I see is - showing Nginx version in error page - nginx/1.8.0. No need to show details of webserver or its version!