A question regarding "everything runs in parallel except your code" from someone new to Node.js. This is an obviously artificial example, but let's say I want to create a math library containing a function factorize() which behaves as follows:
var http = require('http');
http.createServer(function (req, res) {
myMath.factorize(some_big_number,function(factors) {
res.writeHead(200, {'Content-Type': 'application/json'});
res.end(JSON.stringify(factors));
}
}).listen(8000);
How can this be written so that it will "run in parallel"?
I've been looking at the parsing code from this library as an example that might take some processing time. Is the body of the code considered to be "your code", or does this "run in parallel"?
If not: What do I need to do when writing factorize() so that it is also non-blocking/behaves like a client? Is using EventEmitter sufficient?
If so: Is my best option still to use child processes as suggested in this question?
Apologies in advance for any lack of clarity.
Actually you can't run it "parallel" (unless you use a workers module) as JavaScript in node.js is executed in single thread but you can split your single thread into smaller pieces. For example with process.nextTick, so when the CPU is executing the code as smaller chunks instead of one long running code, it has small breaks to run other things as well.
myLongRunningCode(callback){
do_a_piece_of_the_work();
if(ready){
callback();
}else{
// give the CPU a small break to do other things
process.nextTick(function(){
// continue working
myLongRunningCode(callback);
});
}
}