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Child Process

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Child Process

Child Process sits in production box. Farhan’s job is use all CPU cores. Write that first.

For Child Process, an Express route is in play. Don’t blame it until you have traced use all CPU cores.

Without Child Process, production box gets messy and use all CPU cores is hard to trust.

Use Child Process when use all CPU cores must stay clear. If a simpler Node.js step works, use that instead.

Child Process miss — in-memory session without sticky. Fix it before you talk about advanced Node.js.

Place Child Process next to nearby Node.js work — cluster.fork or PM2 is the link.

Close Child Process with — “If I skip it, use all CPU cores goes wrong like this: in-memory session without sticky.”

Exam tip

Board: use all CPU cores. Dry-run Child Process. Name the trap: in-memory session without sticky.

Example

// Child Process
const users = [
  { id: 1, name: "Asha" },
  { id: 2, name: "Ravi" },
];

function findUser(id) {
  return users.find((u) => u.id === id) ?? null;
}

console.log(findUser(2));
console.log(users.map((u) => u.name));

Child Process: find user 2, then list names. Say both prints.

Short notes

DefChild Process — Farhan uses it for use all CPU cores in production box.
RuleChild Process → cluster.fork or PM2.
RememberChild Process + an Express route (production box).
UseChild Process in production box (use all CPU cores).
TrapChild Process — in-memory session without sticky.
ExChild Process → use all CPU cores.

// Child Process const users = [ { id: 1, name: "Asha" }, { id: 2, name: "Ravi" }, ]; function findUser(id) { return users.find((u) => u.id === id) ?? null; } console.log(findUser(2)); console.log(users.map((u) => u.name));

Child Process

Example

Short notes

Questions

Child Process

Example

Short notes

Questions