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    <p>I think, what you want is:</p> <pre><code>function foo() { while (count &lt; 10) { process.nextTick(doSometing); count ++; } } </code></pre> <p><code>process.nextTick</code> will schedule the execution of <code>doSometing</code> on the next tick of the event loop. So, instead of switching immediately to <code>doSometing</code> this code will just schedule the execution and complete <code>foo</code> first.</p> <p>You may also try <code>setTimeout(doSometing,0)</code> and <code>setImmediate(doSometing)</code>. They'll allow <code>I/O</code> calls to occur before <code>doSometing</code> will be executed.</p> <h1>Passing arguments to <code>doSomething</code></h1> <p>If you want to pass some parameters to <code>doSomething</code>, then it's best to ensure they'll be encapsulated and won't change before <code>doSomething</code> will be executed:</p> <pre><code>setTimeout(doSometing.bind(null,foo,bar),0); </code></pre> <p>In this case <code>doSometing</code> will be called with correct arguments even if <code>foo</code> and <code>bar</code> will be changed or deleted. But this won't work in case if <code>foo</code> is an object and you changes one of its properties.</p> <h1>What the alternatives are?</h1> <p>If you want <code>doSomething</code> to be executed in parallel (not just asynchronous, but actually in parallel), then you may be interested in some job-processing solution. I recommend you to look at <a href="https://github.com/verbling/kickq" rel="nofollow">kickq</a>:</p> <pre><code>var kickq = require('kickq'); kickq.process('some_job', function (jobItem, data, cb) { doSomething(data); cb(); }); // ... function foo() { while (count &lt; 10) { kickq.create('some_job', data); count ++; } } </code></pre> <p><code>kickq.process</code> will create a separate process for processing your jobs. So, <code>kickq.create</code> will just register the job to be processed.</p> <p><code>kickq</code> uses <a href="http://redis.io/" rel="nofollow">redis</a> to queue jobs and it won't work without it.</p> <h1>Using node.js build-in modules</h1> <p>Another alternative is building your own job-processor using <a href="http://nodejs.org/api/child_process.html" rel="nofollow">Child Process</a>. The resulting code may look something like this:</p> <pre><code>var fork = require('child_process').fork, child = fork(__dirname + '/do-something.js'); // ... function foo() { while (count &lt; 10) { child.send(data); count ++; } } </code></pre> <p><code>do-something.js</code> here is a separate <code>.js</code> file with <code>doSomething</code> logic:</p> <pre><code>process.on('message', doSomething); </code></pre> <p>The actual code may be more complicated.</p> <h1>Things you should be aware of</h1> <p><code>Node.js</code> is single-threaded, so it executes only one function at a time. It also can't utilize more then one CPU.</p> <p>Node.js is asynchronous, so it's capable of processing multiple functions at once by switching between them. It's really efficient when dealing with functions with lots of <code>I/O</code> calls, because it's newer blocks. So, when one function waits for the response from DB, another function is executed. But <code>node.js</code> is not a good choice for blocking tasks with heavy CPU utilization.</p> <p>It's possible to do real parallel calculations in <code>node.js</code> using modules like <a href="http://nodejs.org/api/child_process.html" rel="nofollow">child_process</a> and <a href="http://nodejs.org/api/cluster.html" rel="nofollow">cluster</a>. <code>child_process</code> allows you to start a new <code>node.js</code> process. It also creates a communication channel between parent and child processes. Cluster allows you to run a cluster of identical processes. It's really handy when you're dealing with <code>http</code> requests, because <code>cluster</code> can distribute them randomly between workers. So, it's possible to create a cluster of workers processing your data in parallel, though generally <code>node.js</code> is single-threaded.</p>
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    1. POexecute a function parallely, while completing execution of rest of the code
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    1. CO@Lenoid I know process.nextTick() will work. But nextTick() executes queued event before any I/O. see here: http://stackoverflow.com/questions/16220710/understanding-the-node-js-event-queue-and-process-nexttick. Here foo() is a I/O call and I wanted to doSomething() to get executed in background and next foo() starts execution. But nextTick() will make all the queued doSomething() to get executed, before starting next foo().
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    2. COUse `setTimeout` then. It won't block `I/O` operations.
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    3. CO@ Leonid Probably that can help
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