KLone – C on Rails!
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
<html> <head><title>Hello Lady!</title></head> <body> <% io_printf(out, "Hey, Lady! You call him Dr. Jones!"); %> </body> </html>
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:
<html>
<head><title>Hello World</title></head>
<body>
<%
int i;
for(i=0; i < 10; ++i) {
io_printf(out, "Hello Lady! %d<br />", i);
}
%>
</body>
</html>
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; i<niter; i++) {
x = (double)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.
You have generated static content, which can be cached. You can always create native modules for ruby very easily, if it is too slow for you: http://www.swig.org/
@teki321: Yes, this is a static example, but with some small modifications it would be dynamic. I am aware of the possibility of Ruby C extensions and SWIG, but I find this more pleasant to work with.
Totally agree with you Hank, it’s pretty easy to work with it, with something more complicated it won’t be so easy, but for this moment why not?!