Cluster nodejs

1. What is cluster in Nodejs?
2. Is it possible to cluster Node processes?
3. What is event loop in Nodejs?
4. What is node mon?
5. What is PM2 in node JS?
6. Why we use child process in node JS?
7. Which choice is not a node global object?
8. Which object is used to manage the cache of required modules Nodejs?
9. What is instance in cluster?
10. What is the purpose of N API?
11. Can we pause EMR cluster?
12. What is a car instrument cluster?

What is cluster in Nodejs?

A cluster is a pool of similar workers running under a parent Node process. Workers are spawned using the fork() method of the child_processes module. This means workers can share server handles and use IPC (Inter-process communication) to communicate with the parent Node process.

Is it possible to cluster Node processes?

To take advantage of multi-core systems, the user will sometimes want to launch a cluster of Node. js processes to handle the load. The cluster module allows easy creation of child processes that all share server ports.

What is event loop in Nodejs?

Event loop is an endless loop, which waits for tasks, executes them and then sleeps until it receives more tasks. The event loop executes tasks from the event queue only when the call stack is empty i.e. there is no ongoing task. The event loop allows us to use callbacks and promises.

What is node mon?

nodemon is a tool that helps develop node. js based applications by automatically restarting the node application when file changes in the directory are detected. ... nodemon is a replacement wrapper for node . To use nodemon , replace the word node on the command line when executing your script.

What is PM2 in node JS?

PM2: A production process manager for Node. js applications that has a built-in load balancer. PM2 enables you to keep applications alive forever, reloads them without downtime, helps you to manage application logging, monitoring, and clustering. ... Includes a CLI to build, package, and deploy Node.

Why we use child process in node JS?

Usually, Node. js allows single-threaded, non-blocking performance but running a single thread in a CPU cannot handle increasing workload hence the child_process module can be used to spawn child processes. The child processes communicate with each other using a built-in messaging system.

Which choice is not a node global object?

The top-level scope is not the global scope; var something inside an Node. js module will be local to that module. And in your code when you write: console.

Which object is used to manage the cache of required modules Nodejs?

_load performs the loading of new modules and manages the cache. On a file loading request, it will first check the file in cache. If module is not found in the cache, this will create a new base module instance for the required file.

What is instance in cluster?

Instances have one or more clusters, located in different zones. Each cluster has at least 1 node. A table belongs to an instance, not to a cluster or node. If you have an instance with more than one cluster, you are using replication. ... You also can't make each cluster store a different set of data in the same table.

What is the purpose of N API?

Node-API (formerly N-API) is an API for building native Addons. It is independent from the underlying JavaScript runtime (for example, V8) and is maintained as part of Node. js itself. This API will be Application Binary Interface (ABI) stable across versions of Node.

Can we pause EMR cluster?

1 Answer. At this time there is not a way to STOP and EMR cluster in the same sense you can with EC2 instances. The EMR cluster uses instance-store volumes and the EC2 start/stop feature relies on the use of EBS volumes which are not appropriate for high-performance, low-latency HDFS utilization.

What is a car instrument cluster?

A car's instrument cluster houses the various displays and indicators that enable a driver to operate the vehicle. Among these are several gauges – often a speedometer, odometer, tachometer, oil pressure gauge, fuel gauge, etc. – as well as various indicators for system malfunctions and warnings.