Thread Pools & Schedulers

After the dependency scheduler, executors are among the most common of Rubrik's concurrency prompts. You get work to run later, or a set of workers to keep busy, and the built-ins are off the table. With no ExecutorService and no BlockingQueue, you build the piece from a lock and a condition variable, and it has to compile and run on CoderPad.

Three of them come up most, and two newer, rarer prompts round out the set. Each keeps a small piece of shared state, and the work is keeping it right as tasks start and finish.

The code runner on this page can't catch a race, so each problem turns the threads into calls you make in order: submit a task, start it, finish it, move the clock. A thread that would block comes back as false or takes a place in a line. Get that single-threaded model passing first, then add locks. The follow-up under each problem puts the lock and the condition variable back in.

RubrikPremium lesson · Coding round

The 5 Rubrik problems are below.

1. 1A Premium questionCoding · Medium · Signature problem
2. 2A Premium questionCoding · Medium · Signature problem
3. 3A Premium questionCoding · Medium · Frequently asked

+ 2 more in this lesson

Each with hints, the follow-up and a tested solution.

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From 202 Rubrik reports, forum threads behind logins and write-ups in Chinese.

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