I’ve been using memcached for a couple years now and it’s by far one of the most useful open source tools. It’s written by Brad Fitzpatrick of livejournal, and used by everyone from, yahoo to facebook.

It so good because does one thing and it does it very well: It provides a distributed in memory cache.

Its super fast and super reliable, and it makes speeding up your site or application simple.

The server is written in c and uses libevent which is an highly scalable, asyncronous event based polling library which allows it to support tens of thousands of concurrent connections.

The client protocol is compact and there are clients in almost every language. The client libraies do most of the work since they can compress the data that goes into memcached and maintain multiple connections to different memcached instances running on your network (this is why the cache is distributed).

One of the few problems I’ve had with memcached have todo with the c based memcache clients libmemcache and apr_memcache.

libmemcache has problems corking the socket in linux, since it’s written for bsd. I’ve had reliability problems under high load where the client garbles the protocol.

apr_memcache works but the memcached protocol isn’t fully supported and it requires apr, which is a dependancy I’d rather not build into a non apache service.

Plus, I really wanted a OO api to use since I’m writing in c++ not c.

So I built memcache++ about a year ago, based origionally on a now defunct c++ client called memcachedpp.

Now that we have launched third rail, I now have a place to release memcache++ so grab it here:

http://3.rdrail.net/code/memcache++

Please send me a mail if you have problems with it, or if you are using it. I’m using it on a few projects with great success!

-Jake

Rich and I recently created third rail as a place to share our ideas and work. We’ve built a number of sites together but we’ve never been very serious about it until now. We both have full time jobs and I’ve got a new baby to worry about, but we’ve defiantly caught a startup bug. I’ve recently worked at a serious web2.0 startup with millions of dollars in funding but I left it because I knew there was no real business there. Just a bunch of random features and social mashups thrown in a pretty ui. I’m not looking to get funded, I don’t want to become the next google. I just want to work for myself and make great software ( and millions of dollars would be nice). So thats it! we’re starting a startup! consider it started. We even have our first killer idea being worked on (in stealth mode)

When I first read about the facebook platform last week I have to admit I wasn’t all that excited. Sure it’s great to see facebook open its doors to 3rd parties, but I’m not itching to code the next social slideshow widget. What’s got got me all fired up however, is something else facebook launched a couple of months ago which largely went unnoticed, called Thrift. It’s what they built their platform with.

Thrift is essentially a framework for building web services that can be accessed by most languages. It’s similar to CORBA in that you define a interface file and thrift will generate stubs implementing that interface in any of it’s supported languages.

• C++
• PHP
• Python
• Java
• Ruby
• And recently Perl (thanks to us)

Once you have these stubs you can build the service backend in the above language of your choice and access it from any of the other languages.

This brings us to rule #1 of programming. Knowing when to use the right tool for the right job.

You would (hopefully) never write a web frontend layer in c++ when php was built specifically for that purpose. You would also (hopefully) never build a search engine backend in php since it will be difficult to maximize performance while minimizing memory and cpu time.

So with thrift you can build the search engine in c++ and access it via php (which is what facebook does).

The default transport mechanism is a compact binary format but its fully extensible to any format (xml,json).

But thats just the beginning. You can do some really cool things with Thrift, like log all messages to file and play them back (instant redo logs). Version your data structures so you can still keep backwards compatibility with older stored data.

Thrift comes with some top notch c++ code to quickly build scalable backend c++ services. We are using thrift today as the search backend for junkdepot.com.

I hope to start a series of artcles on how to use Thrift as an alternative to standard LAMP. I really think thrift will become the backbone of next generation web services. We also will be releasing some of the services we’ve built with thrift as open source projects soon.

Feel free to ask questions.

-Jake