Facebook internals

The code leaked during a facebook bug was posted online by an anonymous user. Though the source itself didn't look very damaging, it did damage the brand "facebook". But I won't go into that in this post, and instead I would like to discus the facebook internals here which alex.moskalyuk touched upon.

Alex pointed out that this is not the only code from facebook we have seen. Infact we already know a lot more about how facebook works internally than what most of us would find from the source code to the index.php published yesterday.

  1. PHP - This is no surprise. Though PHP is not developed at faceboook, Alex points out that facebook developers are involved atleast at some level in the development of the php.

  2. Apache - Neither should this be

  3. Mysql - Same here..

  4. Valgrind - This is a suite of tools for debugging and profiling Linux programs. With the tools that come with Valgrind, you can automatically detect many memory management and threading bugs, avoiding hours of frustrating bug-hunting, making your programs more stable. You can also perform detailed profiling, to speed up and reduce memory use of your programs. Other tools related to this which they user are callgrind/Calltree , KCachegrind and OProfile.

  5. APC - Facebook developers have talked about using Alternative PHP Cache in some presentations they have given in the past.

  6. Facebook Thrift - Thrift is a software framework for scalable cross-language services development. It combines a powerful software stack with a code generation engine to build services that work efficiently and seamlessly between C++, Java, Python, PHP, and Ruby. Thrift was developed at Facebook, and its been released as open source. More information can be found in this whitepaper.

  7. Memcached is a high-performance, distributed memory object caching system, generic in nature, but intended for use in speeding up dynamic web applications by alleviating database load. The use of this shouldn't come as a surprise since most of the new web2.0 companies, especially the ones using php and python have experimented or implemented it at some level.

  8. phpsh is another interesting tool facebook developers use internally. It is an interactive shell for php that features readline history, tab completion, quick access to documentation. It is ironically written mostly in python.

  9. Facebook has released a lot of code to support the facebook platform and to get users to develop for it.

  10. Facebook firefox plugin is the last one I'd like to mention here. This again is open source (since you can see the code once you open up the plugin yourself).


References

Comments

PHP Architectures that power your favourite big websites - TechEnclave said…
[...] Digg uses LAMPDigg ArchitectureDigg PHP's Scalability and Performance FacebookPHP's APC at FacebookFacebook Internals TechEnclave ,and tens of thousands of other forums (Comparison of Internet forum software using [...]
7:09 AM
Internals of Facebook | thoughts and ideals of an internet magnate | Don Wilson said…
[...] a great post regarding the internals of facebook by a blog entitled Scalable web architectures. Interesting, [...]
3:31 PM
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