Facebook makes HipHop for PHP open source

http://developers.facebook.com/news.php?blog=1&story=358

by ivankirigin • 16 years ago

315 190 16 years ago

developers.facebook.com

Quarrelsome• 16 years ago

So it converts PHP into C++?!? Woaw.

Didn't people accuse Joel Spolsky of jumping the shark for doing that kind of thing (Wasabi script => php or vbscript).

.....wait this means that Wasabi can now technically convert into C++! :D

kamens• 16 years ago

We Fog Creek developers were just mentioning this hilarious possibility.

andrewvc• 16 years ago

Well, from what I've heard its more like FB had a mountain of PHP they couldn't ever rewrite, so they made PHP faster by turning it into C++.

Fog Creek rewrote everything in a brand new language they invented that compiles down into multiple other languages.

So, in actuality, the projects are the exact opposite of each other.

tedunangst• 16 years ago

Actually, the point of Wasabi was to avoid rewriting anything.

tghw3• 16 years ago

Fog Creek didn't really rewrite anything. In fact, that was the whole point of Wasabi, to not rewrite anything.

Wasabi did extend VBScript to add objects and other language features, which were gradually incorporated into the code base, but just on changes going forward.

So, really, it is almost exactly the same thing.

gecko• 16 years ago

Cute, but completely wrong.

Wasabi started out as a VBScript -> PHP compiler, allowing us to keep the existing FogBugz source, but run it on Unix and Linux, where ASP wasn't available. Once we had that, it hit us that it'd be pretty easy to add a VBScript -> VBScript compiler, at which point we could add language extensions. So we did. This allowed new code to take advantage of things like macros, better declaration syntax, lambdas and so on, without rewriting any existing code. Finally, because it was clear that ASP was dead, and specifically because we didn't want to rewrite FogBugz from scratch, we modified Wasabi to target .NET.

The whole point of Wasabi was to avoid rewriting FogBugz to support other platforms and technologies. I have no idea where you got the idea we rewrote the entire program; if we'd done that, we'd have just done it in C#.

hypermatt• 16 years ago

Whats even worse is fog creek uses .net now, so it even makes less sense to have your own proprietary language.

mseebach7• 16 years ago

I think where most people chokes on Wasabi is the perception of compiling from an "insane" language to a sane language. No matter how cool it is to work at Fog Creek, it's very 1965 to work in a proprietary language, especially for web development. If Joel wasn't famous, anyone leaving Fog Creek would have serious problems finding a new job.

Facebook compiles from a "sane" language (PHP) to a less sane, but twice as fast language (C++). The alternative was to get their devs to work in C++, which they decided was an unattractive solution -- this seems reasonable.

sker• 16 years ago

PHP is sane?

tghw3• 16 years ago

PHP is somehow a more sane language than classic ASP? They are contemporaries of each other, and both were pretty popular in their day. PHP has continued, while ASP has been replaced by something significantly better than either.

P.S. If the company you're applying to is upset by you having worked in a proprietary language, they're hiring for the wrong things.

runT1ME4• 16 years ago

I wish someone would invent some sort of C-like language that wasn't as complicated.

Maybe it could even compile itself on the fly to machine code to continually optimize itself!

acangiano2• 16 years ago

> from a "sane" language (PHP) to a less sane, but twice as fast language (C++)

C++ is much faster than PHP, not just twice as fast.

statictype• 16 years ago

> No matter how cool it is to work at Fog Creek, it's very 1965 to work in a proprietary language, especially for web development

So you're basically against the use of Domain Specific Languages on the whole? Or only those whose syntax you don't like?

encoderer2• 16 years ago

If you're hiring developers based on experience with a specific language, you're probably doing it wrong anyway.

Hire based on experience with a specific paradigm. OO. Functional. Etc. Or experience with a specific domain problem. Compilers. DSLs. Operating Systems. Etc.

bitwize• 16 years ago

So it converts PHP into C++?!? Woaw.

Joey Lawrence?!

pvg• 16 years ago

There's a pretty big difference between converting a very widely used language to C++ for performance reasons and inventing an entirely new language (which converts to some other, very similar language) for the purposes of tackling the unique and fundamental problems that arise when writing a bug tracker. Difference being only one of these is tremendously silly.

aditya• 16 years ago

I wonder if it'll let you convert things out of the box or if it was optimized for the way php is written at facebook. (eg. it doesn't support eval() but eval() is bad anyway)

Also, how hard would it be to do the same thing for Ruby and Perl? I'm sure there have been other attempts at compilers, but as noted elsewhere, having FB behind it makes HipHop more stable...

Oh, and atleast one thing from this anonymous interview came true: http://therumpus.net/2010/01/conversations-about-the-interne...

daeken• 16 years ago

I wrote a PHP->C++ compiler and bits and pieces of the standard library many moons ago (BinaryPHP: http://sourceforge.net/projects/binaryphp/ ), and it really wasn't terribly difficult, even for a complete compiler novice. We didn't do the fancy optimization that HipHop does, but it worked fairly well at the time. The actual compiler would probably only take a month or two (disregarding real optimizations) for a talented developer or two, but the runtime (assuming it doesn't share anything with PHP proper -- don't know if this does or not) would take much, much longer.

Doing it for Ruby or Python would be fairly straightforward to get running initially, but doing Perl<=5 would be impossible (for all cases) due to it being proven impossible to statically parse.

viraptor2• 16 years ago

You can compile any code - full static parsing doesn't have anything to do with that. If you have a place that is not possible to parse one way, you do a switch on the condition that causes the parsing choice. Then you compile each branch assuming that code was parsed in a specific way.

raganwald2• 16 years ago

how hard would it be to do the same thing for Ruby... ?

Much harder, but not impossible. The two issues are (a) how much of Ruby the language can be compiled to C++ using Type Inference, and (b) For the stuff that can't be compiled, how often does it show up in production code?

FB's PHP solution relies on having a large code base with few instances of code that doesn't compile cleanly.

With Ruby, I suspect both issues are a problem. I think there's a lot more of Ruby the language that will be difficult to infer, and furthermore I think Ruby programmers tend to use those features a lot.

That's just a guess, mind you. You could probably do a lot if you make some major breaks with tradition. For example, if instead of compiling Ruby source code you load Ruby classes, run all the meta-programming, then reverse-engineer the source (ParseTree can do this with Ruby 1.8 but not Ruby 1.9), you could basically do the meta-programming in interpreted mode but run the resulting code in compiled mode.

I suspect that would work well for a lot of Rails programs where the hairiest stuff is run when classes are loaded, not on the fly when responses are being served.

rufugee2• 16 years ago

Wouldn't the challenge in ruby be the prevalence of things you just can't and don't do in PHP? Thinks like instance_eval, class_eval, etc....in Ruby projects I've worked on (and especially in Rails), these are all over the place.

Of course, assuming these calls all happen on the front end (source load) and not downstream in response to some triggering event, your approach would probably work.

fizx• 16 years ago

Does this make more sense than targeting LLVM? It doesn't seem easier to maintain, and you won't get the advantages of the optimizations/work already done.

notaddicted• 16 years ago

g++ has a few optimizations http://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html

spoondan• 16 years ago

I doubt he was somehow ignorant of the fact that g++ optimizes its generated code. I believe his point was that great work has already been done on optimizing compilers for dynamic languages targeting LLVM (c.f., Unladen Swallow and Rubinius).

orblivion• 16 years ago

Was just thinking the same thing. "Man, I guess it works, but isn't it weird that they're generating what's probably hard to read C++ just to get fast machine code? Eventually they should make a language just for the purpose of optimizing. Oh wait."

alxv• 16 years ago

According to the Unladen Swallow's team [1], LLVM's "just-in-time infrastructure was relatively untested and buggy" when they started working with it. So, I think not using LLVM was a pragmatic decision. In addition, debugging C++ code is much easier than dealing with intricacies of dynamically generated machine code.

[1] http://www.python.org/dev/peps/pep-3146/#performance-retrosp...

kingkilr• 16 years ago

Yes, but it's not now. Unladen Swallow isn't exactly alone in blazing this trail, Rubinius is using LLVM as well.

wmf• 16 years ago

HipHop is a static compiler, though. That part of LLVM seems to have been heavily exercised by GCC and Clang.

malkia• 16 years ago

Well maybe The Facebook guys were not only after speed optimization, but memory too. No matter how great the LLVM JIT is it probably uses some memory to compile the code, and this way wasting some amount. Static compilation would not waste this amount.

I'm actually proponent of JIT, over static compilation, but only for my little pet projects.

I don't know much about WEB, but for games development, static compilation is sometimes the only way to go (or script interpretation). Sometimes there is just not enough memory, and sometimes it's restricted (hell, it so much resticted that you can't change the VTABLE at runtime in C++ class even if you want to)

ricardo_sdl• 16 years ago

GitHub were crushed by the release of HipHop. Too bad, I wished to test the HipHop translator.

icco• 16 years ago

Their file servers crashed before the Hip Hop announcement, and Hip Hop hasn't even been pushed to GitHub yet, according to this announcement.

http://twitter.com/github/status/8551643423

euroclydon• 16 years ago

What CGI mechanism are they using to host a blended PHP/C++ code base?

teoruiz• 16 years ago

I guess they transform complete PHP libraries to C++, they build them and then they "require" them from some other PHP code.

KrisJordan3• 16 years ago

"It has it's own built-in web server when you compile it, via libevent." from Ben Ramsey who attended the demo at FB Campus.

maxklein7• 16 years ago

I really could not justify not doing web stuff in PHP anymore. PHP is THE web language. No, Ruby is not going to take over, and no, python is not going to take over.

Those two would have been the main contenders for the space, but they both had their shot and their 15 minutes of fame, and rather than rapidly growing to dominate web development, they nichified.

PHP however is being improved, being cleaned up, and most importantly, being speed optimised.

PHP is what you can trivially easily outsource - try to do that with python or ruby.

This right here is basically the move that is going to cement PHP as the web language. The largest sites are using PHP and are going to stay with PHP. Nothing will take over from PHP. The battle is over.

Zak4• 16 years ago

PHP is what you can trivially easily outsource

Yes, you can... but be careful - you might end up with this: http://paste.lisp.org/display/76132

That's real production code I removed from an application I was hired to extend and debug. Eventually, I convinced the client to scrap it and let me write a replacement with Rails.

ams6110• 16 years ago

Sadly that resembles most of the ASP/PHP code I've ever worked with.

The very low barriers to entry of PHP and ASP means you have (had) a lot of very inexperienced folks writing code.

That said, I agree with the original point that PHP can be very productive. No compiles, no builds... just edit code/refresh browser to immediately see the effect of a change. That's nice if you have the discipline to not do stuff like the linked example.

sailormoon7• 16 years ago

Nice troll, but there are a ton of websites being developed in Ruby/Rails these days. I don't think it's nichified at all, and the number of job ads is going up, not down.

Ruby is being improved and sped up too, in case you hadn't noticed.

As always, use the best tool for the job. For an awful lot of small business sites - where PHP got its start - that is now Rails, and it's slowly emerging in larger projects too. I think Ruby will definitely give PHP a run for its money in the fullness of time.

maxklein7• 16 years ago

That's what you believe. I believe something different. I believe that these languages had the chance, and it didn't happen. Technology rarely gets a second chance without some type of major change.

grandalf3• 16 years ago

There are a few narrow cases where I'd choose to do a project in PHP, but very few.

It is possible to write nice clean code in PHP, but few apps I've ever seen do so. Most use includes like function calls all over the place, so there is no notion of what variables will be used or defined inside the included code.

Ruby to some extent, and especially Python, are designed so that your code looks good and is easy to read. Admittedly some people can write highly obfuscated Ruby, but that (fortunately) went out of style a few years ago.

maxklein7• 16 years ago

The average programmer does not use Ruby or Python. He uses Java, PHP or C. And the programming world is dependent on the average programmer.

ryanwaggoner• 16 years ago

I don't agree with you, but I find it sad that your comment has been voted down below 0. Is this what HN has come to? We just vote stuff we don't agree with down?

jonursenbach• 16 years ago

That's the point of the karma system.

spudlyo4• 16 years ago

People might have voted the comment down because they thought it was obvious trolling. Personally I'm not interested in yet another conversation on merits of PHP vs other scripting languages.

Kilimanjaro• 16 years ago

The writing is on the wall, javascript is THE web language, php will be THE legacy web language.

The train is just leaving the station, be sure to get the best seats.

maxklein7• 16 years ago

I actually agree with you. Javascript is next in line. But it's not yet its turn. It will come soon, though, but what's the point in jumping off the dock on a boat when the boat has not arrived yet?

_pius4• 16 years ago

Are you serious? I'm not trying to be flippant, but I literally can't tell if you're joking or not.

maxklein7• 16 years ago

Yes I am serious. The most widely used and supported web language is likely to remain the dominant language on the web and will not be surpassed by tiny niche languages.

That statement is one I would describe as reasonable.

henrikschroder• 16 years ago

Obligatory: http://i.imgur.com/1gF1j.jpg

carson2• 16 years ago

It would seem they forgot to make the project public on github.

andymism• 16 years ago

Third paragraph from the bottom of the post says they'll be releasing the source in Github this evening (probably pacific time).

carson2• 16 years ago

Ahhh, they should have held off on that wiki link.

Erwin• 16 years ago

This sounds rather similar in principle to Python's Shedskin compiler, which turns ordinary Python code in C++ code, using C++-based runtime replacing the ordinary Python runtime. This works extremely very well on a certain class of problems. http://code.google.com/p/shedskin/

mrshoe• 16 years ago

I see this as being useful if you already have these two things:

1) A large PHP codebase and

2) A CPU-bound app with scaling issues

If you're starting a new app, I don't see why you would choose PHP. And I think most web apps are database-bound rather than CPU-bound. HipHop seems incredibly useful for Facebook, but are other people here on HN excited about using it?

lanstein• 16 years ago

I have a CLI application that's IO-bound. I'm extremely excited. Furthermore, I'm sure this is exciting to anyone who has deployed Memcache, and now has an application that is CPU-bound.

ighost3• 16 years ago

I wish memcache changed my IO bound app to CPU bound.

ivankirigin4• 16 years ago

You can optimize on multiple fronts. Just because facebook needs to scale data access doesn't mean it shouldn't scale processing time too. As the post mentioned, this has had a huge impact. [i work at facebook, comments on this site are my own opinion, and I'm not intimately involved in the project]

But generally I agree about new projects. If you have a favorite language, use it.

coliveira2• 16 years ago

There is no need to switch to PHP only for this reason, but there is a huge number of apps already using PHP. It will be a great benefit to them. Also, it will become another factor for people considering developing a new application: if a language can quickly be converted to C++, this is easier than writing extensions in C/C++ directly.

mikeryan• 16 years ago

I think this is where many run into issues with this story. This project was never really meant to be something to help the PHP community as a whole. It was meant to be a tool to help Facebook and to that end they've succeeded very well. 3 engineers + 2 years = 50% CPU improvement without having to rewrite the whole PHP codebase from scratch? That's a great achievement for Facebook but YMMV.

staunch• 16 years ago

Seriously. $100k * 3 devs * 2 years = $600k to buy half as many app servers in the next year(s)? They saved Facebook tens of millions of dollars. I should imagine their next performance evaluation will be quite smooth.

This is what people mean when they talk about great hackers being 10x as productive...

pmjordan• 16 years ago

With HipHop we've reduced the CPU usage on our Web servers on average by about fifty percent, depending on the page.

Hmm. I'm guessing they're comparing it to their PHP stack that has already had the living daylights optimized out of it (with cached bytecode, etc.) and/or a large proportion of their pages doesn't hit much code (lots of stuff cached?). I'd have thought there would be more mileage in this.

grandalf3• 16 years ago

It seems odd to me that anyone thinks PHP is "easy".

The syntax is odd, as is the behavior of the built-in functions (many retain seriously warts from older versions of PHP)

It's "easy" in the sense that you just edit one file and the webpage changes, but if that's a stumbling block for your developers then you have bigger problems.

coliveira2• 16 years ago

It is really easy if you already have experience with C++. Also, it is not very different from UNIX shell, and it is clearer than Perl, so I don't get why people complain so much about it.

jrockway5• 16 years ago

Everything is easy if you have experience with C++.

I fail to see how PHP is clearer than Perl. It may have fewer special characters, but everything is done with oddly-named functions that take positional arguments in an inconsistent order, return error codes instead of throwing exceptions, and randomly spew warning messages.

From a language design standpoint... there is no design. Perl may not be perfect either, but the design has been flexible enough to radically modify as the community sees fit. Or rather, how you choose to modify it, as most modifications are modular and only affect a single lexical scope. Oh.

grandalf3• 16 years ago

There is just so much needless complexity and oddness, consider the way arrays contain a pointer (so that they can work like a stack) which has crazy odd behavior (which changes depending on which version of PHP you use) when you copy the array..

robryan4• 16 years ago

PHP is "easy" because anyone can grab some code snippets, rewrite some mysql_query's and have a terrible little my first dynamic website doing in a couple of hours.

Developing something on a large scale or even developing something of a normal size while maintaining good programming techniques and structure can be difficult.

blasdel• 16 years ago

How templatey is the generated code? How big are the resulting binaries?

Amazon's original core platform (obidos) was written in C++ and deployed as one monolithic binary. I've heard that one of the major things pushing their Java rewrite (dp) was that the binary no longer fit comfortably into memory!

prewett• 16 years ago

Just curious, but how is Java going to solve that problem? Now you've got the Java opcodes, plus any JIT information/native code, plus the JVM. Seems like that would be even larger!

spudlyo4• 16 years ago

I can't wait to try to try this out on a large PHP codebase like Drupal and then run some benchmarks. It'd be interesting to see how much faster it is when compared to vanilla PHP vs opcode cached PHP.

runT1ME4• 16 years ago

Facebook's lack of engineering prowess continually amazes me.

There were quite a few other options aside from writing a translator.

sailormoon7• 16 years ago

Are you living in an alternate universe? Facebook are scarily competent. They have executed brilliantly and their engineering is top notch.

runT1ME4• 16 years ago

Really? You mean like their ultra-reliable chat server they wrote?

Or maybe the way their replication works, so when you post things get out of order depending on what server you are looking at?

spudlyo4• 16 years ago

Agreed. I'm impressed by the great stuff coming out of Facebook. Cassandara, Scribe, Thrift, etc.

codexon4• 16 years ago

I am sad to see Facebook helping to perpetuate PHP.

On the bright side though, even if HipHop yields a 50% speedup, it is unlikely to be faster than Python, Javascript V8, or LuaJit.

http://shootout.alioth.debian.org/u32/chartbox.php?s=eNo9ktu...

edit

What's with the downvotes? I can't mention my opinions on php?

ivankirigin4• 16 years ago

Use your imagination. Perhaps other languages can be compiled down with HipHop. Perhaps other languages can call PHP libraries compiled with HipHop. Then you might have an end to end solution to transition from PHP to Python.

This is obviously just a fantasy of mine. Back to coding PHP...

codexon4• 16 years ago

> Perhaps other languages can be compiled down with HipHop.

There's already something like HipHop for Python called Cython. You can compile any pure python code into a static C shared library (with the exception of generators).

h0h0h0• 16 years ago

Damnit - a cool project name wasted on a php to c++ compiler?? DJ Kool Herc is disgusted with Facebook.

erickerr• 16 years ago

They probably just use a python script and type

from php import cppCompiler

not sure why that took 2 years

jrockway5• 16 years ago

This is truly the PHP solution to the problem. Design a virtual machine that uses runtime information to generate highly-optimized native code? Nahh.... just regex the source into C++, compile with g++, and enjoy!

(To be fair, some language implementations have achieved good results with this method; notably Chicken scheme. But I was expecting something better and potentially more useful to the language implementation community at large.)

Raphael• 16 years ago

C++ is known to be fast, so what advantage could a more complex solution provide?

jrockway5• 16 years ago

Not having to wait fifteen minutes for your app to compile and link, for one thing. But seriously, the C++ implementation comes at the cost of many of PHP's features; a "more complex solution" would allow those features to be kept. And while C++ is fast, a script translated into C++ is not going to be as fast as if you had written the application directly in C++, unless the compiler is very, very smart. (I have not seen any implementation that does this; GHC's native code generator produces faster code than it's "via-C" code generator, for example.)

Also, static compilation precludes runtime-based optimization techniques, which has made a lot of code run "faster than C" (including C, ironically; see LLVM).

So anyway, all this is is a way to compile a limited subset of PHP to C++. In doing so, you have to write a special dialect of PHP, without PHP's easy deployability and code/test/debug cycle.

In that case, why are you using PHP to begin with, when a language like GHC or SBCL would run faster and without any compromises?

evlapix• 16 years ago

If this is adopted widely hosting costs will drop off considerably, no?

mbreese4• 16 years ago

So, does this mean that PHP has officially forked? I mean who is going to want to keep writing in the interpreted version as opposed to the hiphop-able version? How many changes are there? I've only seen mentions of ditching eval, but there is probably more. Will people be debugging their code in both vanilla PHP and HPHP?

How well does this support other projects, like wordpress (for example)?

Another issue this raises is who is now in control of PHP? Not in legal terms, but in terms of mindshare. It's one this for a student to write a PHP translator, but quite another for Facebook to do it. I'll be interested to see how Zend responds to this. At least when Google started unladen swallow, they had Guido working for them.

qeorge• 16 years ago

No, you'll probably see no changes in your day to day life as a result of this. There's no "interpreted version as opposed to the hiphop-able version", in terms of the code you write.

As the article mentions, almost no one is really running straight PHP, they're running it through FastCGI or are at least using an opcode cache like APC. So you could be swapping out APC for HPHP, but this is at a level of abstraction below the one you're working in.

Regarding future control of PHP, this does not change anything. Its a compiler for the language, but does not propose any changes to the language itself.

mbreese4• 16 years ago

you'll probably see no changes in your day to day life as a result of this

I'm fairly confident about that... I gave up PHP years ago :)

KrisJordan3• 16 years ago

Some details not in the official announcement:

Currently works off of the PHP 5.2 language specs

Compiles to a stand-alone libevent-driven web server or CLI executable

Not based on Zend's runtime/code

Currently no windows support

Intended for 'drop in' PHP replacement - if it runs on PHP and doesn't use a few things like eval() it will compile with HipHop

jrockway5• 16 years ago

Intended for 'drop in' PHP replacement - if it runs on PHP and doesn't use a few things like eval() it will compile with HipHop

This sounds a lot like Python's 2to3. This technique worked so well that the Python 2 series is a distant memory of the past.

(Oh wait... the opposite.)

tlack2• 16 years ago

Did they reimplement the entire standard PHP library bug-for-bug in C++? I'm curious about that aspect of it..

JoachimSchipper2• 16 years ago

Why would they need to do that? The standard library is a mix of PHP, which they can already handle, and C, which doesn't have to be rewritten.

icey• 16 years ago

Hmm, this is one of those rare occasions where something has been released where I have a domain name that could be useful - hiphoperator.com

Now I just have to figure out what to do with it :D

ohashi• 16 years ago

at least 1 youtube video

peter_o• 16 years ago

Will this be faster than less say... python?

tlrobinson2• 16 years ago

"HipHop for PHP isn't technically a compiler itself."

...

"HipHop programmatically transforms your PHP source code into highly optimized C++"

Sounds like a compiler to me. Compilers don't have to target machine code.

DrJokepu2• 16 years ago

Exactly my thoughts. To further support your statement, theoretically, it should be possible to create a CPU that interprets C++ source code as machine code (not sure why would anyone do that though.)

jrockway5• 16 years ago

A better example is modern x86 CPUs. You feed them x86 instructions, but that is not the native language of the CPU; everything is translated into the real underlying (RISC) language as the x86 instructions are encountered.

Or so I'm told. I've never read Intel's source code :)

EricBurnett2• 16 years ago

By that logic then PHP itself is also assembly because someone could make a machine that executes it natively. We might as well throw all distinctions away if we go down this road.

bkudria• 16 years ago

Exactly. The textbook definition of a compiler is a program that translates a program from one language to another.

codexon4• 16 years ago

Here's a quote from an alleged Facebook employee on Reddit regarding this matter.

This entire thread needs to go fall in a well and die. If they had just called it a compiler, you nerds would be arguing about the same thing and saying it was a source code transformer. They just called it that because it translates PHP to C++, and to most people who don't have Asperger's that's not the same as compiling.

How do I know this? I sit 20 feet from the guys who wrote it.

http://www.reddit.com/r/programming/comments/ax7k4/facebooks...

tlrobinson2• 16 years ago

I'm not sure how working 20 feet from the guy makes him an authority on how us "nerds" would react.

Anyway, the thing that got me was the "technically", otherwise I may have let it slide. You could argue it's not a compiler in the commonly accepted sense of the word, but technically it most certainly is a compiler.

icefox• 16 years ago

"300,000 lines of code and more than 5,000 unit tests."

Both values sound good in theory, but are both meaningless. How is the code coverage? How many man months? How many developers?

henning• 16 years ago

I find it ironic that you feel LOC is meaningless and then asked for man-months, an even more useless unit of measurement :D

0wned• 16 years ago

After this, can we still make fun of C++? I use it daily and love it. Sure, it takes someone with a brain to use it, but once you learn C++, nothing else comes close for speed and expressiveness... seems FaceBook just verified that. So while people who cannot code in C++ will still talk about it as if they know it, it continues to kick ass in solving real-world computing problems

tptacek• 16 years ago

Facebook appears to be using C++ the way C++ devs use assembly. We can definitely continue making fun of it.

nir3• 16 years ago

Remember when the meme was "%90 of web apps will not reach a point where scaling is an issue"? Well, of those who do reach it, %90 will not reach a point when PHP's execution (assuming you use on of the existing code accelerator, all which are free IIRC and one will be bundled with PHP6) is the bottleneck.

It's a cool hack, but really targets Facebook-level needs. For most users, the downside (eg compatibility issues) will far outweigh the benefits.

rythie3• 16 years ago

Actually it's an efficiency gain, rather than scalability. Facebook already have a system they can add more servers at, but this is designed to let them use less and save money as a result.

Also at least 90% of web apps are tiny or are startups that never made it, either way they don't need this for a long time, like you say.

nir3• 16 years ago

efficiency -> scalability, in the sense that serving the request faster will free the server to serve another request.

My point is that for nearly all apps, executing PHP is very small part of the total request handling time, so even a significant improvement will have little overall effect. I bet many people excited by HipHop could get a much bigger performance gain by adding some simple caching)

necro• 16 years ago

Though I agree that most single sites wont benefit from this. We have a single site serving 100 pages/sec and php is not even close to becoming a bottleneck.

The other application where this may be helpful is the cloud. In a system like this you have 100s or 1000s of sites on a single machine that may reach the combined traffic where this optimization can come into play.

viraptor2• 16 years ago

Or when you pay per cpu cycles / memory. If you can reduce that usage, then your costs are directly affected.

encoderer2• 16 years ago

You might be surprised in some cases.... We recently did some tsung testing on an optimization system we've developed (purposely general here).

Running it the developers workstation w/ APC and Memcache and local Percona MySQL, it maxed at 300 request/s. (It's just a workstation, remember). Anyway, there may be some observer effects here, but the profiler indicated that most the time was being spent on php functions and system calls.

So we might be in the 1% you're describing. Or _maybe_ it's a more than 1% after all.

gojomo• 16 years ago

Will Wikipedia, Wikia, and other major MediaWiki sites use this? (Does MediaWiki code use eval()?)

Perceval• 16 years ago

I would bet that Wikipedia is more database bound than CPU bound. HipHop would probably help, but not tremendously.

sailormoon7• 16 years ago

You reckon? I would have thought Wikipedia a textbook case for a great big cache. I would have guessed that the great majority of their views were read-only by unregistered users, with the pages in question following a power law distribution. Hm, would be interested to find out more about that.

update: I went and looked it up. They do indeed have a great big cache, many of them in fact. In fact their Amsterdam presence runs only cache! From what I can tell, it seems their bottleneck is actually Apache, and presumably a lot of that is PHP.

Interesting presentation here: http://wikimania2009.wikimedia.org/w/index.php?title=Media:R...

Also check this out: http://ganglia.wikimedia.org/pmtpa/?gw=fwd&gs=Wikimedia%...

Go down to the MySQL section. Plenty of headroom, but the Apaches are working hard.

KrisJordan3• 16 years ago

Some notes from Facebook's UStream event this evening: http://www.recessframework.org/page/notes-from-facebooks-hip...

High points:

the performance numbers were against PHP with APC op-code caching enabled

eval, create_function, and preg_replace with /e (basically eval), and conditional flow based on the existance of functions are the only features not supported.

Currently PHP5.2 with a roadmap of 5.2.12 compliant in the next month and 5.3 being the focus after that.

regularfry• 16 years ago

If this makes a big difference to memory footprint, won't it be rather handy to embedded devs?

agazso• 16 years ago

Where is the link to download it or just the documentation? On the announcement page there is only a Wiki link (besides wikipedia entries and other php-to-other-lang compilers) to a Github page that redirects to the github.com.

ojbyrne• 16 years ago

So... stupid question - Where's the code? It's the next day and no sign of it on github.

Facebook makes HipHop for PHP open source

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