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I was hoping to create my own in-house analytics so I tell my customers how many visits their company page got on my site and which URL they came from. I am coding this in Python (Flask) and I wondered if anyone could tell me what is the standard, or sensible approach to this problem.
I think it might be to have some sort of Redis queue which is triggered when a visitor comes and then this information is added to the database later so the site doesn't seem slow.
The standard, and sensible approach is to use Google Analytics. If you must roll your own, you have one of two approaches. JavaScript that is executed on every page (like GA) and pulls this kind of info into a DB. The second approach is parsing log files on the server. Awstats is a good bet for that.
I've searched on google and have taken a look at the facebook site for the apis, but facebook does not have an official SDK for python. I looked at the third party api for python listed on their site that could be used to communicate with facebook. After having visited their official site and github repository there is a small readme file that shows basic usage, it seems to assume that you are already connected to facebook, and the example at the end of that page shows a cookie example.
The short examples seem easy enough but there is no explaination of anything and i dont find any more documentation about anything else.. there does not seem to be any information about all available methods you can use with the api..where do the people who are using this api get the documentation to find the methods available so they are able to do work with this ?
Since i guess people are pretty tired of signing up for yet another service i would like to offer to sign in with their facebook and twitter accounts (although thats a no no for the ad people who would like to have access to the user profile in order to have targeted words/links that generate revenue). Im using django and have taken a look at the django-facebook api as well but the documentation seems to just point to the github repository which doesnt have any documenation, almost just like the other api pointed out above. Basically i dont find any documenation about how to use the apis except from the small examples.
And like always, i appericiate your time answering this, always nice to add an explaination to any code so the answer is a little more usefull, thanks.
My info might be a little bit out of date as I was working at a startup implementing a Python backend on Google AppEngine that interfaced with Facebook, used FQL, AppEngine datastore etc, about a year and half ago.
There are several third party APIs you can use, for instance, https://github.com/jgorset/facepy or https://github.com/pythonforfacebook/facebook-sdk. The reason there is no 'documentation' on the github site is because it implements access to the API that IS documented on Facebook's developer pages https://developers.facebook.com/docs/graph-api/.
But that is in a perfect world. My experience with the Facebook APIs is that they don't always do what is said on the dev pages. You don't get consistent return data, FB Realtime API not/inconsistently notifying for certain connections (music, movies, books, tv). Unfortunately, I think they have many non-documented APIs that are only available to the big app players.
Where I got my real world working info and learned how to access Facebook using Python was right here on stack overflow.
I'm trying to find a solution to my current problem. Let me explain: I need to find a Search UI that can consume a REST service of my choice and be highly configurable. I've searched the web and found Blacklight Search UI (written in Ruby) for Solr. I've also looked at Haystack (for django) which seems to be more promissing because somewhere in the docs i found out that you can link Haystack to your custom search engine. Out of the box Haystack supports Solr, Xapian and 2 others which i can't remember now.
What i'm trying to find is a UI written in Java, PHP(last resort!) or Python that will allow me to specify the endpoints for my APIs and with a few configurations (i'm not expecting it to run out of the box) it should be able to query the APIs and return results.
If that is not possible then could somebody suggest me something that gets close to what I described and allows me to write my own backend code that will link to the APIs ? A Haystack example will also do...
Thanks
I'm interested in this topic as well. I know about the SESAT framework supporting FAST, Solr, Yahoo!, generic XML and more, but it is old and not well maintained, and also tries to do much more than a simple front-end.
You also have AJAX-Solr which obviously only supports Solr.
I have forwarded your question on Twitter, hope others will fill in as well.
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I'm building a web application with Django. The reasons I chose Django were:
I wanted to work with free/open-source tools.
I like Python and feel it's a long-term language, whereas regarding Ruby I wasn't sure, and PHP seemed like a huge hassle to learn.
I'm building a prototype for an idea and wasn't thinking too much about the future. Development speed was the main factor, and I already knew Python.
I knew the migration to Google App Engine would be easier should I choose to do so in the future.
I heard Django was "nice".
Now that I'm getting closer to thinking about publishing my work, I start being concerned about scale. The only information I found about the scaling capabilities of Django is provided by the Django team (I'm not saying anything to disregard them, but this is clearly not objective information...).
My questions:
What's the "largest" site that's built on Django today? (I measure size mostly by user traffic)
Can Django deal with 100,000 users daily, each visiting the site for a couple of hours?
Could a site like Stack Overflow run on Django?
"What are the largest sites built on Django today?"
There isn't any single place that collects information about traffic on Django built sites, so I'll have to take a stab at it using data from various locations. First, we have a list of Django sites on the front page of the main Django project page and then a list of Django built sites at djangosites.org. Going through the lists and picking some that I know have decent traffic we see:
Instagram: What Powers Instagram: Hundreds of Instances, Dozens of Technologies.
Pinterest: Alexa rank 37 (21.4.2015) and 70 Million users in 2013
Bitbucket: 200TB of Code and 2.500.000 Users
Disqus: Serving 400 million people with Python.
curse.com: 600k daily visits.
tabblo.com: 44k daily visits, see Ned Batchelder's posts Infrastructure for modern web sites.
chesspark.com: Alexa rank about 179k.
pownce.com (no longer active): alexa rank about 65k.
Mike Malone of Pownce, in his EuroDjangoCon presentation on Scaling Django Web Apps says "hundreds of hits per second". This is a very good presentation on how to scale Django, and makes some good points including (current) shortcomings in Django scalability.
HP had a site built with Django 1.5: ePrint center. However, as for novemer/2015 the entire website was migrated and this link is just a redirect. This website was a world-wide service attending subscription to Instant Ink and related services HP offered (*).
"Can Django deal with 100,000 users daily, each visiting the site for a couple of hours?"
Yes, see above.
"Could a site like Stack Overflow run on Django?"
My gut feeling is yes but, as others answered and Mike Malone mentions in his presentation, database design is critical. Strong proof might also be found at www.cnprog.com if we can find any reliable traffic stats. Anyway, it's not just something that will happen by throwing together a bunch of Django models :)
There are, of course, many more sites and bloggers of interest, but I have got to stop somewhere!
Blog post about Using Django to build high-traffic site michaelmoore.com described as a top 10,000 website. Quantcast stats and compete.com stats.
(*) The author of the edit, including such reference, used to work as outsourced developer in that project.
We're doing load testing now. We think we can support 240 concurrent requests (a sustained rate of 120 hits per second 24x7) without any significant degradation in the server performance. That would be 432,000 hits per hour. Response times aren't small (our transactions are large) but there's no degradation from our baseline performance as the load increases.
We're using Apache front-ending Django and MySQL. The OS is Red Hat Enterprise Linux (RHEL). 64-bit. We use mod_wsgi in daemon mode for Django. We've done no cache or database optimization other than to accept the defaults.
We're all in one VM on a 64-bit Dell with (I think) 32Gb RAM.
Since performance is almost the same for 20 or 200 concurrent users, we don't need to spend huge amounts of time "tweaking". Instead we simply need to keep our base performance up through ordinary SSL performance improvements, ordinary database design and implementation (indexing, etc.), ordinary firewall performance improvements, etc.
What we do measure is our load test laptops struggling under the insane workload of 15 processes running 16 concurrent threads of requests.
Not sure about the number of daily visits but here are a few examples of large Django sites:
disqus.com (talk from djangocon)
bitbucket.org (write up)
lanyrd.com (source)
support.mozilla.com (source code)
addons.mozilla.org (source code) (talk from djangocon)
theonion.com (write up)
The guardian.co.uk comment system uses Django (source)
instagram
pinterest
rdio
Here is a link to list of high traffic Django sites on Quora.
What's the "largest" site that's built on Django today? (I measure size mostly by user traffic)
In the US, it was Mahalo. I'm told they handle roughly 10 million uniques a month. Now, in 2019, Mahalo is powered by Ruby on Rails.
Abroad, the Globo network (a network of news, sports, and entertainment sites in Brazil); Alexa ranks them in to top 100 globally (around 80th currently).
Other notable Django users include PBS, National Geographic, Discovery, NASA (actually a number of different divisions within NASA), and the Library of Congress.
Can Django deal with 100k users daily, each visiting the site for a couple of hours?
Yes -- but only if you've written your application right, and if you've got enough hardware. Django's not a magic bullet.
Could a site like StackOverflow run on Django?
Yes (but see above).
Technology-wise, easily: see soclone for one attempt. Traffic-wise, compete pegs StackOverflow at under 1 million uniques per month. I can name at least dozen Django sites with more traffic than SO.
Scaling Web apps is not about web frameworks or languages, is about your architecture.
It's about how you handle you browser cache, your database cache, how you use non-standard persistence providers (like CouchDB), how tuned is your database and a lot of other stuff...
Playing devil's advocate a little bit:
You should check the DjangoCon 2008 Keynote, delivered by Cal Henderson, titled "Why I hate Django" where he pretty much goes over everything Django is missing that you might want to do in a high traffic website. At the end of the day you have to take this all with an open mind because it is perfectly possible to write Django apps that scale, but I thought it was a good presentation and relevant to your question.
The largest django site I know of is the Washington Post, which would certainly indicate that it can scale well.
Good design decisions probably have a bigger performance impact than anything else. Twitter is often cited as a site which embodies the performance issues with another dynamic interpreted language based web framework, Ruby on Rails - yet Twitter engineers have stated that the framework isn't as much an issue as some of the database design choices they made early on.
Django works very nicely with memcached and provides some classes for managing the cache, which is where you would resolve the majority of your performance issues. What you deliver on the wire is almost more important than your backend in reality - using a tool like yslow is critical for a high performance web application. You can always throw more hardware at your backend, but you can't change your users bandwidth.
I was at the EuroDjangoCon conference the other week, and this was the subject of a couple of talks - including from the founders of what was the largest Django-based site, Pownce (slides from one talk here). The main message is that it's not Django you have to worry about, but things like proper caching, load balancing, database optimisation, etc.
Django actually has hooks for most of those things - caching, in particular, is made very easy.
I'm sure you're looking for a more solid answer, but the most obvious objective validation I can think of is that Google pushes Django for use with its App Engine framework. If anybody knows about and deals with scalability on a regular basis, it's Google. From what I've read, the most limiting factor seems to be the database back-end, which is why Google uses their own...
As stated in High Performance Django Book
and Go through this Cal Henderson
See further details as mentioned below:
It’s not uncommon to hear people say “Django doesn’t scale”. Depending on how you look at it, the statement is either completely true or patently false. Django, on its own, doesn’t scale.
The same can be said of Ruby on Rails, Flask, PHP, or any other language used by a database-driven dynamic website.
The good news, however, is that Django interacts beautifully with a suite of caching and
load balancing tools that will allow it to scale to as much traffic as you can throw at it.
Contrary to what you may have read online,
it can do so without replacing core components often labeled as “too slow” such as the database ORM or the template layer.
Disqus serves over 8 billion page views per month. Those are some huge numbers.
These teams have proven Django most certainly does scale.
Our experience here at Lincoln Loop backs it up.
We’ve built big Django sites capable of spending the day on the Reddit homepage without breaking a sweat.
Django’s scaling success stories are almost too numerous to list at this point.
It backs Disqus, Instagram, and Pinterest. Want some more proof? Instagram was able to sustain over 30 million users on Django with only 3 engineers (2 of which had no back-end development
Today we use many web apps and sites for our needs. Most of them are highly useful. I will show you some of them used by python or django.
Washington Post
The Washington Post’s website is a hugely popular online news source to accompany their daily paper. Its’ huge amount of views and traffic can be easily handled by the Django web framework.
Washington Post - 52.2 million unique visitors (March, 2015)
NASA
The National Aeronautics and Space Administration’s official website is the place to find news, pictures, and videos about their ongoing space exploration. This Django website can easily handle huge amounts of views and traffic.
2 million visitors monthly
The Guardian
The Guardian is a British news and media website owned by the Guardian Media Group. It contains nearly all of the content of the newspapers The Guardian and The Observer. This huge data is handled by Django.
The Guardian (commenting system) - 41,6 million unique visitors (October, 2014)
YouTube
We all know YouTube as the place to upload cat videos and fails. As one of the most popular websites in existence, it provides us with endless hours of video entertainment. The Python programming language powers it and the features we love.
DropBox
DropBox started the online document storing revolution that has become part of daily life. We now store almost everything in the cloud. Dropbox allows us to store, sync, and share almost anything using the power of Python.
Survey Monkey
Survey Monkey is the largest online survey company. They can handle over one million responses every day on their rewritten Python website.
Quora
Quora is the number one place online to ask a question and receive answers from a community of individuals. On their Python website relevant results are answered, edited, and organized by these community members.
Bitly
A majority of the code for Bitly URL shortening services and analytics are all built with Python. Their service can handle hundreds of millions of events per day.
Reddit
Reddit is known as the front page of the internet. It is the place online to find information or entertainment based on thousands of different categories. Posts and links are user generated and are promoted to the top through votes. Many of Reddit’s capabilities rely on Python for their functionality.
Hipmunk
Hipmunk is an online consumer travel site that compares the top travel sites to find you the best deals. This Python website’s tools allow you to find the cheapest hotels and flights for your destination.
Click here for more:
25-of-the-most-popular-python-and-django-websites,
What-are-some-well-known-sites-running-on-Django
I think we might as well add Apple's App of the year for 2011, Instagram, to the list which uses django intensively.
Yes it can. It could be Django with Python or Ruby on Rails. It will still scale.
There are few different techniques. First, caching is not scaling. You could have several application servers balanced with nginx as the front in addition to hardware balancer(s).
To scale on the database side you can go pretty far with read slave in MySQL / PostgreSQL if you go the RDBMS way.
Some good examples of heavy traffic websites in Django could be:
Pownce when they were still there.
Discus (generic shared comments manager)
All the newspaper related websites: Washington Post and others.
You can feel safe.
Here's a list of some relatively high-profile things built in Django:
The Guardian's "Investigate your MP's expenses" app
Politifact.com (here's a Blog post talking about the (positive) experience. Site won a Pulitzer.
NY Times' Represent app
EveryBlock
Peter Harkins, one of the programmers over at WaPo, lists all the stuff they’ve built with Django on his blog
It's a little old, but someone from the LA Times gave a basic overview of why they went with Django.
The Onion's AV Club was recently moved from (I think Drupal) to Django.
I imagine a number of these these sites probably gets well over 100k+ hits per day. Django can certainly do 100k hits/day and more. But YMMV in getting your particular site there depending on what you're building.
There are caching options at the Django level (for example caching querysets and views in memcached can work wonders) and beyond (upstream caches like Squid). Database Server specifications will also be a factor (and usually the place to splurge), as is how well you've tuned it. Don't assume, for example, that Django's going set up indexes properly. Don't assume that the default PostgreSQL or MySQL configuration is the right one.
Furthermore, you always have the option of having multiple application servers running Django if that is the slow point, with a software or hardware load balancer in front.
Finally, are you serving static content on the same server as Django? Are you using Apache or something like nginx or lighttpd? Can you afford to use a CDN for static content? These are things to think about, but it's all very speculative. 100k hits/day isn't the only variable: how much do you want to spend? How much expertise do you have managing all these components? How much time do you have to pull it all together?
The developer advocate for YouTube gave a talk about scaling Python at PyCon 2012, which is also relevant to scaling Django.
YouTube has more than a billion users, and YouTube is built on Python.
I have been using Django for over a year now, and am very impressed with how it manages to combine modularity, scalability and speed of development. Like with any technology, it comes with a learning curve. However, this learning curve is made a lot less steep by the excellent documentation from the Django community. Django has been able to handle everything I have thrown at it really well. It looks like it will be able to scale well into the future.
BidRodeo Penny Auctions is a moderately sized Django powered website. It is a very dynamic website and does handle a good number of page views a day.
Note that if you're expecting 100K users per day, that are active for hours at a time (meaning max of 20K+ concurrent users), you're going to need A LOT of servers. SO has ~15,000 registered users, and most of them are probably not active daily. While the bulk of traffic comes from unregistered users, I'm guessing that very few of them stay on the site more than a couple minutes (i.e. they follow google search results then leave).
For that volume, expect at least 30 servers ... which is still a rather heavy 1,000 concurrent users per server.
My experience with Django is minimal but I do remember in The Django Book they have a chapter where they interview people running some of the larger Django applications. Here is a link. I guess it could provide some insights.
It says curse.com is one of the largest Django applications with around 60-90 million page views in a month.
What's the "largest" site that's built on Django today? (I measure size mostly by user traffic)
Pinterest
disqus.com
More here: https://www.shuup.com/en/blog/25-of-the-most-popular-python-and-django-websites/
Can Django deal with 100,000 users daily, each visiting the site for a couple of hours?
Yes but use proper architecture, database design, use of cache, use load balances and multiple servers or nodes
Could a site like Stack Overflow run on Django?
Yes just need to follow the answer mentioned in the 2nd question
I don't think the issue is really about Django scaling.
I really suggest you look into your architecture that's what will help you with your scaling needs.If you get that wrong there is no point on how well Django performs. Performance != Scale. You can have a system that has amazing performance but does not scale and vice versa.
Is your application database bound? If it is then your scale issues lay there as well. How are you planning on interacting with the database from Django? What happens when you database cannot process requests as fast as Django accepts them? What happens when your data outgrows one physical machine. You need to account for how you plan on dealing with those circumstances.
Moreover, What happens when your traffic outgrows one app server? how you handle sessions in this case can be tricky, more often than not you would probably require a shared nothing architecture. Again that depends on your application.
In short languages is not what determines scale, a language is responsible for performance(again depending on your applications, different languages perform differently). It is your design and architecture that makes scaling a reality.
I hope it helps, would be glad to help further if you have questions.
Another example is rasp.yandex.ru, Russian transport timetable service. Its attendance satisfies your requirements.
If you have a site with some static content, then putting a Varnish server in front will dramatically increase your performance. Even a single box can then easily spit out 100 Mbit/s of traffic.
Note that with dynamic content, using something like Varnish becomes a lot more tricky.
I develop high traffic sites using Django for the national broadcaster in Ireland. It works well for us. Developing a high performance site is more than about just choosing a framework. A framework will only be one part of a system that is as strong as it's weakest link. Using the latest framework 'X' won't solve your performance issues if the problem is slow database queries or a badly configured server or network.
The problem is not to know if django can scale or not.
The right way is to understand and know which are the network design patterns and tools to put under your django/symfony/rails project to scale well.
Some ideas can be :
Multiplexing.
Inversed proxy. Ex : Nginx, Varnish
Memcache Session. Ex : Redis
Clusterization on your project and db for load balancing and fault tolerance : Ex : Docker
Use third party to store assets. Ex : Amazon S3
Hope it help a bit. This is my tiny rock to the mountain.
Even-though there have been a lot of great answers here, I just feel like pointing out, that nobody have put emphasis on..
It depends on the application
If you application is light on writes, as in you are reading a lot more data from the DB than you are writing. Then scaling django should be fairly trivial, heck, it comes with some fairly decent output/view caching straight out of the box. Make use of that, and say, redis as a cache provider, put a load balancer in front of it, spin up n-instances and you should be able to deal with a VERY large amount of traffic.
Now, if you have to do thousands of complex writes a second? Different story. Is Django going to be a bad choice? Well, not necessarily, depends on how you architect your solution really, and also, what your requirements are.
Just my two cents :-)
If you want to use Open source then there are many options for you. But python is best among them as it has many libraries and a super awesome community.
These are a few reasons which might change your mind:
Python is very good but it is a interpreted language which makes it slow. But many accelerator and caching services are there which partly solve this problem.
If you are thinking about rapid development then Ruby on Rails is best among all. The main motto of this(ROR) framework is to give a comfortable experience to the developers. If you compare Ruby and Python both have nearly the same syntax.
Google App Engine is very good service but it will bind you in its scope, you don't get chance to experiment new things. Instead of it you can use Digital Ocean cloud which will only take $5/Month charge for its simplest droplet. Heroku is another free service where you can deploy your product.
Yes! Yes! What you heard is totally correct but here are some examples which are using other technologies
Rails: Github, Twitter(previously), Shopify, Airbnb, Slideshare, Heroku etc.
PHP: Facebook, Wikipedia, Flickr, Yahoo, Tumbler, Mailchimp etc.
Conclusion is a framework or language won't do everything for you. A better architecture, designing and strategy will give you a scalable website. Instagram is the biggest example, this small team is managing such huge data. Here is one blog about its architecture must read it.
You can definitely run a high-traffic site in Django. Check out this pre-Django 1.0 but still relevant post here: http://menendez.com/blog/launching-high-performance-django-site/
Check out this micro news aggregator called EveryBlock.
It's entirely written in Django. In fact they are the people who developed the Django framework itself.
Spreading the tasks evenly, in short optimizing each and every aspect including DBs, Files, Images, CSS etc. and balancing the load with several other resources is necessary once your site/application starts growing. OR you make some more space for it to grow. Implementation of latest technologies like CDN, Cloud are must with huge sites. Just developing and tweaking an application won't give your the cent percent satisfation, other components also play an important role.
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I'm building a web application with Django. The reasons I chose Django were:
I wanted to work with free/open-source tools.
I like Python and feel it's a long-term language, whereas regarding Ruby I wasn't sure, and PHP seemed like a huge hassle to learn.
I'm building a prototype for an idea and wasn't thinking too much about the future. Development speed was the main factor, and I already knew Python.
I knew the migration to Google App Engine would be easier should I choose to do so in the future.
I heard Django was "nice".
Now that I'm getting closer to thinking about publishing my work, I start being concerned about scale. The only information I found about the scaling capabilities of Django is provided by the Django team (I'm not saying anything to disregard them, but this is clearly not objective information...).
My questions:
What's the "largest" site that's built on Django today? (I measure size mostly by user traffic)
Can Django deal with 100,000 users daily, each visiting the site for a couple of hours?
Could a site like Stack Overflow run on Django?
"What are the largest sites built on Django today?"
There isn't any single place that collects information about traffic on Django built sites, so I'll have to take a stab at it using data from various locations. First, we have a list of Django sites on the front page of the main Django project page and then a list of Django built sites at djangosites.org. Going through the lists and picking some that I know have decent traffic we see:
Instagram: What Powers Instagram: Hundreds of Instances, Dozens of Technologies.
Pinterest: Alexa rank 37 (21.4.2015) and 70 Million users in 2013
Bitbucket: 200TB of Code and 2.500.000 Users
Disqus: Serving 400 million people with Python.
curse.com: 600k daily visits.
tabblo.com: 44k daily visits, see Ned Batchelder's posts Infrastructure for modern web sites.
chesspark.com: Alexa rank about 179k.
pownce.com (no longer active): alexa rank about 65k.
Mike Malone of Pownce, in his EuroDjangoCon presentation on Scaling Django Web Apps says "hundreds of hits per second". This is a very good presentation on how to scale Django, and makes some good points including (current) shortcomings in Django scalability.
HP had a site built with Django 1.5: ePrint center. However, as for novemer/2015 the entire website was migrated and this link is just a redirect. This website was a world-wide service attending subscription to Instant Ink and related services HP offered (*).
"Can Django deal with 100,000 users daily, each visiting the site for a couple of hours?"
Yes, see above.
"Could a site like Stack Overflow run on Django?"
My gut feeling is yes but, as others answered and Mike Malone mentions in his presentation, database design is critical. Strong proof might also be found at www.cnprog.com if we can find any reliable traffic stats. Anyway, it's not just something that will happen by throwing together a bunch of Django models :)
There are, of course, many more sites and bloggers of interest, but I have got to stop somewhere!
Blog post about Using Django to build high-traffic site michaelmoore.com described as a top 10,000 website. Quantcast stats and compete.com stats.
(*) The author of the edit, including such reference, used to work as outsourced developer in that project.
We're doing load testing now. We think we can support 240 concurrent requests (a sustained rate of 120 hits per second 24x7) without any significant degradation in the server performance. That would be 432,000 hits per hour. Response times aren't small (our transactions are large) but there's no degradation from our baseline performance as the load increases.
We're using Apache front-ending Django and MySQL. The OS is Red Hat Enterprise Linux (RHEL). 64-bit. We use mod_wsgi in daemon mode for Django. We've done no cache or database optimization other than to accept the defaults.
We're all in one VM on a 64-bit Dell with (I think) 32Gb RAM.
Since performance is almost the same for 20 or 200 concurrent users, we don't need to spend huge amounts of time "tweaking". Instead we simply need to keep our base performance up through ordinary SSL performance improvements, ordinary database design and implementation (indexing, etc.), ordinary firewall performance improvements, etc.
What we do measure is our load test laptops struggling under the insane workload of 15 processes running 16 concurrent threads of requests.
Not sure about the number of daily visits but here are a few examples of large Django sites:
disqus.com (talk from djangocon)
bitbucket.org (write up)
lanyrd.com (source)
support.mozilla.com (source code)
addons.mozilla.org (source code) (talk from djangocon)
theonion.com (write up)
The guardian.co.uk comment system uses Django (source)
instagram
pinterest
rdio
Here is a link to list of high traffic Django sites on Quora.
What's the "largest" site that's built on Django today? (I measure size mostly by user traffic)
In the US, it was Mahalo. I'm told they handle roughly 10 million uniques a month. Now, in 2019, Mahalo is powered by Ruby on Rails.
Abroad, the Globo network (a network of news, sports, and entertainment sites in Brazil); Alexa ranks them in to top 100 globally (around 80th currently).
Other notable Django users include PBS, National Geographic, Discovery, NASA (actually a number of different divisions within NASA), and the Library of Congress.
Can Django deal with 100k users daily, each visiting the site for a couple of hours?
Yes -- but only if you've written your application right, and if you've got enough hardware. Django's not a magic bullet.
Could a site like StackOverflow run on Django?
Yes (but see above).
Technology-wise, easily: see soclone for one attempt. Traffic-wise, compete pegs StackOverflow at under 1 million uniques per month. I can name at least dozen Django sites with more traffic than SO.
Scaling Web apps is not about web frameworks or languages, is about your architecture.
It's about how you handle you browser cache, your database cache, how you use non-standard persistence providers (like CouchDB), how tuned is your database and a lot of other stuff...
Playing devil's advocate a little bit:
You should check the DjangoCon 2008 Keynote, delivered by Cal Henderson, titled "Why I hate Django" where he pretty much goes over everything Django is missing that you might want to do in a high traffic website. At the end of the day you have to take this all with an open mind because it is perfectly possible to write Django apps that scale, but I thought it was a good presentation and relevant to your question.
The largest django site I know of is the Washington Post, which would certainly indicate that it can scale well.
Good design decisions probably have a bigger performance impact than anything else. Twitter is often cited as a site which embodies the performance issues with another dynamic interpreted language based web framework, Ruby on Rails - yet Twitter engineers have stated that the framework isn't as much an issue as some of the database design choices they made early on.
Django works very nicely with memcached and provides some classes for managing the cache, which is where you would resolve the majority of your performance issues. What you deliver on the wire is almost more important than your backend in reality - using a tool like yslow is critical for a high performance web application. You can always throw more hardware at your backend, but you can't change your users bandwidth.
I was at the EuroDjangoCon conference the other week, and this was the subject of a couple of talks - including from the founders of what was the largest Django-based site, Pownce (slides from one talk here). The main message is that it's not Django you have to worry about, but things like proper caching, load balancing, database optimisation, etc.
Django actually has hooks for most of those things - caching, in particular, is made very easy.
I'm sure you're looking for a more solid answer, but the most obvious objective validation I can think of is that Google pushes Django for use with its App Engine framework. If anybody knows about and deals with scalability on a regular basis, it's Google. From what I've read, the most limiting factor seems to be the database back-end, which is why Google uses their own...
As stated in High Performance Django Book
and Go through this Cal Henderson
See further details as mentioned below:
It’s not uncommon to hear people say “Django doesn’t scale”. Depending on how you look at it, the statement is either completely true or patently false. Django, on its own, doesn’t scale.
The same can be said of Ruby on Rails, Flask, PHP, or any other language used by a database-driven dynamic website.
The good news, however, is that Django interacts beautifully with a suite of caching and
load balancing tools that will allow it to scale to as much traffic as you can throw at it.
Contrary to what you may have read online,
it can do so without replacing core components often labeled as “too slow” such as the database ORM or the template layer.
Disqus serves over 8 billion page views per month. Those are some huge numbers.
These teams have proven Django most certainly does scale.
Our experience here at Lincoln Loop backs it up.
We’ve built big Django sites capable of spending the day on the Reddit homepage without breaking a sweat.
Django’s scaling success stories are almost too numerous to list at this point.
It backs Disqus, Instagram, and Pinterest. Want some more proof? Instagram was able to sustain over 30 million users on Django with only 3 engineers (2 of which had no back-end development
Today we use many web apps and sites for our needs. Most of them are highly useful. I will show you some of them used by python or django.
Washington Post
The Washington Post’s website is a hugely popular online news source to accompany their daily paper. Its’ huge amount of views and traffic can be easily handled by the Django web framework.
Washington Post - 52.2 million unique visitors (March, 2015)
NASA
The National Aeronautics and Space Administration’s official website is the place to find news, pictures, and videos about their ongoing space exploration. This Django website can easily handle huge amounts of views and traffic.
2 million visitors monthly
The Guardian
The Guardian is a British news and media website owned by the Guardian Media Group. It contains nearly all of the content of the newspapers The Guardian and The Observer. This huge data is handled by Django.
The Guardian (commenting system) - 41,6 million unique visitors (October, 2014)
YouTube
We all know YouTube as the place to upload cat videos and fails. As one of the most popular websites in existence, it provides us with endless hours of video entertainment. The Python programming language powers it and the features we love.
DropBox
DropBox started the online document storing revolution that has become part of daily life. We now store almost everything in the cloud. Dropbox allows us to store, sync, and share almost anything using the power of Python.
Survey Monkey
Survey Monkey is the largest online survey company. They can handle over one million responses every day on their rewritten Python website.
Quora
Quora is the number one place online to ask a question and receive answers from a community of individuals. On their Python website relevant results are answered, edited, and organized by these community members.
Bitly
A majority of the code for Bitly URL shortening services and analytics are all built with Python. Their service can handle hundreds of millions of events per day.
Reddit
Reddit is known as the front page of the internet. It is the place online to find information or entertainment based on thousands of different categories. Posts and links are user generated and are promoted to the top through votes. Many of Reddit’s capabilities rely on Python for their functionality.
Hipmunk
Hipmunk is an online consumer travel site that compares the top travel sites to find you the best deals. This Python website’s tools allow you to find the cheapest hotels and flights for your destination.
Click here for more:
25-of-the-most-popular-python-and-django-websites,
What-are-some-well-known-sites-running-on-Django
I think we might as well add Apple's App of the year for 2011, Instagram, to the list which uses django intensively.
Yes it can. It could be Django with Python or Ruby on Rails. It will still scale.
There are few different techniques. First, caching is not scaling. You could have several application servers balanced with nginx as the front in addition to hardware balancer(s).
To scale on the database side you can go pretty far with read slave in MySQL / PostgreSQL if you go the RDBMS way.
Some good examples of heavy traffic websites in Django could be:
Pownce when they were still there.
Discus (generic shared comments manager)
All the newspaper related websites: Washington Post and others.
You can feel safe.
Here's a list of some relatively high-profile things built in Django:
The Guardian's "Investigate your MP's expenses" app
Politifact.com (here's a Blog post talking about the (positive) experience. Site won a Pulitzer.
NY Times' Represent app
EveryBlock
Peter Harkins, one of the programmers over at WaPo, lists all the stuff they’ve built with Django on his blog
It's a little old, but someone from the LA Times gave a basic overview of why they went with Django.
The Onion's AV Club was recently moved from (I think Drupal) to Django.
I imagine a number of these these sites probably gets well over 100k+ hits per day. Django can certainly do 100k hits/day and more. But YMMV in getting your particular site there depending on what you're building.
There are caching options at the Django level (for example caching querysets and views in memcached can work wonders) and beyond (upstream caches like Squid). Database Server specifications will also be a factor (and usually the place to splurge), as is how well you've tuned it. Don't assume, for example, that Django's going set up indexes properly. Don't assume that the default PostgreSQL or MySQL configuration is the right one.
Furthermore, you always have the option of having multiple application servers running Django if that is the slow point, with a software or hardware load balancer in front.
Finally, are you serving static content on the same server as Django? Are you using Apache or something like nginx or lighttpd? Can you afford to use a CDN for static content? These are things to think about, but it's all very speculative. 100k hits/day isn't the only variable: how much do you want to spend? How much expertise do you have managing all these components? How much time do you have to pull it all together?
The developer advocate for YouTube gave a talk about scaling Python at PyCon 2012, which is also relevant to scaling Django.
YouTube has more than a billion users, and YouTube is built on Python.
I have been using Django for over a year now, and am very impressed with how it manages to combine modularity, scalability and speed of development. Like with any technology, it comes with a learning curve. However, this learning curve is made a lot less steep by the excellent documentation from the Django community. Django has been able to handle everything I have thrown at it really well. It looks like it will be able to scale well into the future.
BidRodeo Penny Auctions is a moderately sized Django powered website. It is a very dynamic website and does handle a good number of page views a day.
Note that if you're expecting 100K users per day, that are active for hours at a time (meaning max of 20K+ concurrent users), you're going to need A LOT of servers. SO has ~15,000 registered users, and most of them are probably not active daily. While the bulk of traffic comes from unregistered users, I'm guessing that very few of them stay on the site more than a couple minutes (i.e. they follow google search results then leave).
For that volume, expect at least 30 servers ... which is still a rather heavy 1,000 concurrent users per server.
My experience with Django is minimal but I do remember in The Django Book they have a chapter where they interview people running some of the larger Django applications. Here is a link. I guess it could provide some insights.
It says curse.com is one of the largest Django applications with around 60-90 million page views in a month.
What's the "largest" site that's built on Django today? (I measure size mostly by user traffic)
Pinterest
disqus.com
More here: https://www.shuup.com/en/blog/25-of-the-most-popular-python-and-django-websites/
Can Django deal with 100,000 users daily, each visiting the site for a couple of hours?
Yes but use proper architecture, database design, use of cache, use load balances and multiple servers or nodes
Could a site like Stack Overflow run on Django?
Yes just need to follow the answer mentioned in the 2nd question
I don't think the issue is really about Django scaling.
I really suggest you look into your architecture that's what will help you with your scaling needs.If you get that wrong there is no point on how well Django performs. Performance != Scale. You can have a system that has amazing performance but does not scale and vice versa.
Is your application database bound? If it is then your scale issues lay there as well. How are you planning on interacting with the database from Django? What happens when you database cannot process requests as fast as Django accepts them? What happens when your data outgrows one physical machine. You need to account for how you plan on dealing with those circumstances.
Moreover, What happens when your traffic outgrows one app server? how you handle sessions in this case can be tricky, more often than not you would probably require a shared nothing architecture. Again that depends on your application.
In short languages is not what determines scale, a language is responsible for performance(again depending on your applications, different languages perform differently). It is your design and architecture that makes scaling a reality.
I hope it helps, would be glad to help further if you have questions.
Another example is rasp.yandex.ru, Russian transport timetable service. Its attendance satisfies your requirements.
If you have a site with some static content, then putting a Varnish server in front will dramatically increase your performance. Even a single box can then easily spit out 100 Mbit/s of traffic.
Note that with dynamic content, using something like Varnish becomes a lot more tricky.
I develop high traffic sites using Django for the national broadcaster in Ireland. It works well for us. Developing a high performance site is more than about just choosing a framework. A framework will only be one part of a system that is as strong as it's weakest link. Using the latest framework 'X' won't solve your performance issues if the problem is slow database queries or a badly configured server or network.
The problem is not to know if django can scale or not.
The right way is to understand and know which are the network design patterns and tools to put under your django/symfony/rails project to scale well.
Some ideas can be :
Multiplexing.
Inversed proxy. Ex : Nginx, Varnish
Memcache Session. Ex : Redis
Clusterization on your project and db for load balancing and fault tolerance : Ex : Docker
Use third party to store assets. Ex : Amazon S3
Hope it help a bit. This is my tiny rock to the mountain.
Even-though there have been a lot of great answers here, I just feel like pointing out, that nobody have put emphasis on..
It depends on the application
If you application is light on writes, as in you are reading a lot more data from the DB than you are writing. Then scaling django should be fairly trivial, heck, it comes with some fairly decent output/view caching straight out of the box. Make use of that, and say, redis as a cache provider, put a load balancer in front of it, spin up n-instances and you should be able to deal with a VERY large amount of traffic.
Now, if you have to do thousands of complex writes a second? Different story. Is Django going to be a bad choice? Well, not necessarily, depends on how you architect your solution really, and also, what your requirements are.
Just my two cents :-)
If you want to use Open source then there are many options for you. But python is best among them as it has many libraries and a super awesome community.
These are a few reasons which might change your mind:
Python is very good but it is a interpreted language which makes it slow. But many accelerator and caching services are there which partly solve this problem.
If you are thinking about rapid development then Ruby on Rails is best among all. The main motto of this(ROR) framework is to give a comfortable experience to the developers. If you compare Ruby and Python both have nearly the same syntax.
Google App Engine is very good service but it will bind you in its scope, you don't get chance to experiment new things. Instead of it you can use Digital Ocean cloud which will only take $5/Month charge for its simplest droplet. Heroku is another free service where you can deploy your product.
Yes! Yes! What you heard is totally correct but here are some examples which are using other technologies
Rails: Github, Twitter(previously), Shopify, Airbnb, Slideshare, Heroku etc.
PHP: Facebook, Wikipedia, Flickr, Yahoo, Tumbler, Mailchimp etc.
Conclusion is a framework or language won't do everything for you. A better architecture, designing and strategy will give you a scalable website. Instagram is the biggest example, this small team is managing such huge data. Here is one blog about its architecture must read it.
You can definitely run a high-traffic site in Django. Check out this pre-Django 1.0 but still relevant post here: http://menendez.com/blog/launching-high-performance-django-site/
Check out this micro news aggregator called EveryBlock.
It's entirely written in Django. In fact they are the people who developed the Django framework itself.
Spreading the tasks evenly, in short optimizing each and every aspect including DBs, Files, Images, CSS etc. and balancing the load with several other resources is necessary once your site/application starts growing. OR you make some more space for it to grow. Implementation of latest technologies like CDN, Cloud are must with huge sites. Just developing and tweaking an application won't give your the cent percent satisfation, other components also play an important role.