splitting the load through multiple node processes is fine for simple usecases and in general you're fine if you do mostly IO stuff.
But there are usecases that have to crunch numbers or do other CPU intensive algorithms that can be parallelized on the algorithm level. This is where node.js just falls apart. Additionally, if an algorithm requires quite much memory (multiple gigs), node.js performs very poorly.
Most companies that do actual CPU intensive work have services written in other languages to handle this, and "we're using node!" mostly means that they just serve results or do other IO-Tasks with node. But not the actual work.
But there are usecases that have to crunch numbers or do other CPU intensive algorithms that can be parallelized on the algorithm level. This is where node.js just falls apart. Additionally, if an algorithm requires quite much memory (multiple gigs), node.js performs very poorly.
Most companies that do actual CPU intensive work have services written in other languages to handle this, and "we're using node!" mostly means that they just serve results or do other IO-Tasks with node. But not the actual work.