KLone – C on Rails!

Erik — Sun, 10 Jun 2007 17:13:00 +0000

Well, I was over at Debian Package of the Day when I noticed an article on KLone. It’s a little application framework that allows you to do XHTML templating in C! Then, you can compile it and send it off to any Linux machine (with a few dependencies of course) to run it. I got it, and it didn’t work for me at first. Then, for some reason, it started working. Here’s what I think did it:

In Ubuntu, I did this:


sudo apt-get install build-essential libssl-dev quilt klone klone-package

Then, I made a new test project:


make-klone-project create -p myhello

This creates a new project directory. Now, go into it and make it your new home:


cd myhello-0.1/
cd userdata/
mkdir www etc
vim etc/kloned.conf

I’m just going to assume you’re using vim because, well, you should be. Make the config file look something like this:


server_list my_http
allow_root yes

my_http
{
    type      http
    addr.type IPv4
    addr.port 8880
    dir_root  /www
}

Now lets give it something to work with (note we’re still in userdata):


vim www/index.klone


</span>Hello Lady!<span class="ta">

  <%  io_printf(out, "Hey, Lady!  You call him Dr. Jones!");  %>

Now add your precious files to the sauce:


cd ../../site/
klone -c import ../userdata/
# 2 dirs and 2 files imported
cd ..

Now, compile and run it:


kloned-build -o myapp userdata
./myapp -F  # This runs it in non-daemonized mode

If you don’t get any errors, congratulations. That means I did something right.

Now, just hop over to here or wherever you specified it to run, and it will magically appear.

Now you can do this:



</span>Hello World<span class="ta">

<%
int i;
for(i=0; i < 10; ++i) {
    io_printf(out, "Hello Lady! %d
", i);
}
%>

Then run this to rebuild and re-run the server:


kloned-build -o myapp userdata && ./myapp -F

Update

So, I ran some tests, and I have to say, the speed increase from C might be really awesome every now and again. Here’s the code:


   clock_t curtime = clock();
   #define SEED 35791246
   int niter=10000000;
   double x,y;
   int count=0; /* # of points in the 1st quadrant of unit circle */
   double z;
   double pi;

   /* initialize random numbers */
   srand(SEED);
   count=0;
   for ( i=0; idouble)rand()/RAND_MAX;
      y = (double)rand()/RAND_MAX;
      z = x*x+y*y;
      if (z<=1) count++;
      }
   pi=(double)count/niter*4;
   io_printf(out, "# of trials= %d , estimate of pi is %g \n",niter,pi);
   io_printf(out, "%f", (double)(clock() - curtime)/(double)CLOCKS_PER_SEC);

All this is is a Monte Carlo method of calculating pi that I stole from here. It takes 0.56 seconds of CPU time on my Core 2 Duo @ 3.3Ghz. Now for the Ruby on Rails test:


# Controller
    @start = Time.now
    srand(35791246)
    iter = 10000000
    count = 0
    0.upto(iter) do |i|
      x = rand().to_f
      y = rand().to_f
      z = x*x+y*y
      count += 1 if z <= 1
    end
    @pi = count.to_f / iter * 4
    @end = Time.now

This finishes in 20.75 seconds (about 40x slower). C is great for things like this. I hope to use KLone in the future for these kinds of tasks.

Schadenfreude » klone

KLone – C on Rails!

Update