pre-interview: Got referred by some current OCI employees
education: Tier 1 State University
prior experience: ~4yoe, SDE2 at one of FAANG
1st Round: Tech screening
Recruiter mentioned that this would be a elimination round, if I passed this, a full onsite loop comprising 5 more rounds would be set up.
After the basic intros, interviewer asked which topic(s) should he evaluate me on & asked if I had experience with Java. Even though most of my work exp. is in Java, I don't like language/framework specific questions in a interview setup, so asked him if DS Algorithms was fine by him. He agreed & started questioning.
The first question was a warm up type question related to tree traversals, it was a LC easy in terms of difficulty.
He followed that up with another question that could be solved by standard BFS.
After that he moved to a question which was related to finding out the minumum cost at which a certain task could be carried out. Don't remember the exact question but it was fairly doable. I would say the easier half of LC medium.
I gave a O(n^2) soln. at first which basically proposed searching over the entire solution space linearly & returning the minimum cost which would be a valid solution. Then as an optimisation I pointed out the monotonicity of the search space & suggested a binary search might be better. The binary search solution had a complexity of O(32n)
Interviewer was satisfied & after a day recruiter asked my availability to schedule the onsites.
Coding 1 -
This round was a discussion on this question, was able to solve it. Fumbled a bit in the implementation when was asked to extend the solution to allow duplicates in the the list, but was able to satisfactorily explain my approach to handle the follow-up & interviewer seemed satisfied for the most part. Then interviewer asked me how do I handle blockers or unknows in my project & work around them. I explained my thoughts on the same.
Bar Tender round - This round was taken by a senior Director, it was a very pleasant experience overall. We had a nice discussion on my work portfolio in my resume & he asked to choose any one of them & draw the architecture of the whole system on a whiteboard & asked me various in depth questions related to that. After finishing with those he asked me if I knew how JVM worked. I said I am not an expert on JVM internals but can give you a basic high level overview of how it works and then gave a brief explanation of the internals of JVM, the lifecycle of how java code is compiled & turned into executable bytecode, the memory model & how GC works at a high level. He seemed satisfied & overall I felt I had done good in this round.
System Design - I was asked to design a video streaming website. Started with the FR analysis like uploading video, watching video and then added NFRs on my own like scalability, availability, etc. Had discussions on choice of storage, the APIs required, various kinds of metadata reqd to enable the flows, since my experience is mostly in AWS gave a solution using offerings from that platform like S3 for object storage, any general CDN for content distribution, various kinds of encoding/decoding flows for the various use cases, TCP v UDP for streaming, designing the play bar and discussing various use cases like eager loading upto a certain extent, and how much history of the video to cache locally, etc. I felt this round went well too.
Coding 2 - Was asked a LC hard in this round that I couldn't solve fully.
The question was that given a tree, find the node with the maximum value of a given function f such that f(nX) = for all nodes (sum of (distance of the other node in the tree from nX * value of the node))
sort of similar to https://leetcode.com/problems/sum-of-distances-in-tree/description/
I solved using a brute force BFS which passed only about 60% of the test cases since it was essentially O(n^2) I thought I had bombed this round but apparently OCI focuses more on the ability to keep thinking & iterating over a base solution as oppossed to just churning out the best solution, which is what I did, I tried to come up with a better approach but couldn't in the given one hour.
HM round - Had in depth discussion on my projects, was asked various situational questions, some of it behavorial some technical in nature, and they were basically related to gauging my thought process in production scenarios. Was asked to come up with some basic design choices as per various situation laid out to me. I felt this round went decent too.
After a few days recruiter informed that debrief outcome was +ve & that they would start the process of offer rollout. Recruiter said due to the current market they won't give any hikes & will barely match my current TC. I didn't argue. The process is underway, BGV is done & it has been sometime since then and I have come to know OCI is under a hiring freeze so am not really keeping much hopes from them now. Meanwhile I have found another team at my current company(was a part of layoffs in January) so am staying here for now.
Update - received written offer letter confirmation today https://leetcode.com/discuss/compensation/3299445/Oracle-OCI-or-IC3-or-India-or-2023
Not too inclined on switching at nearly 0% hike