This repo holds my solutions to the gossip glomers Challenges that have a series of challenges built using maelstrom SDK (go and rust). These are a bunch of introductory distributed system challenges that I think give a good first look into dist system. I found them not so challenging. :/
Link to these challenges (I hope they never take these down) : Gossip Glomer Challenges
If for any reason these challenges were to be taken off of the internet, I have the challenges copied to the readme.md in each of the challenged folders, and if they were ever to take down the maelstrom binary, I have a version of the binary in this folder as well.
If they were to take down the maelstrom go SKD, guess what? I have a copy of that in here too xD. All the tests for each of the challenges are part of readme.md in each challenge folder
This is a rather simple challenge of just echoing back all the messages received by a given node. This challenge only exists to get you used to the Maelstrom SDK and runner. I wrote this solution in Rust, back when there was not great support for rust maelstrom SKD. I figured it was making these challenges much harder not in the way these challenges intended, hence I moved to Golang from the next challenge.
Keep the random generating value state space large enough and ye shall pass. Just depends on the probability of the same unique IDs being low. They haven't asked for any growing pattern so why bother, right?
All of these could be achieved in a single solution, I wrote a rather straightforward solution and it worked well.
To make our latencies better, I started using a buffer in between to make them happen.
Used a global KV to solve this challenge.
Here I used a KV service, this is just step one to the harder challenges of using KV. Also, commit messages can be stored only in the local
Here we need to start thinking of recency and guarantees and race conditions.
Here we need to start thinking as to which data resides in which KV! For this, I did not do anything different from 5b as there is no strict test for this challenge and I was stumped for ideas too. Do post your solutions somewhere if u get some simple ideas.
For a single node KV, try not to use a KV provided by Maelstrom. A local KV makes this challenge its worth.
extension of challenge 6a, but now we move a multi-node replicated kV store with a rather weak gaurentee. Read Uncommitted is what is asked of us. In this guarantee, almost anything is allowed. They also want you to check against the partition for total availability.
This is an extension of challenge 6b. Now they still want a multi-node KV store, but a read committed transactional gaurentee is required. Despite only being a small addition, this makes the challenge hard and worthy of a final boss challenge (xD)
The solution is rather simple, the key is [BEWARE BEFORE OPENING, it is worth working out on your own]:
Spoiler warning
Jespen asks for total availability, this is only possible if stale reads are allowed. In this challenge, Jespen accepts all stale reads. To handle intermediated reads make sure to get one lock per transaction and not break up the transaction.
Sequential consistency is a strong safety property for concurrent systems. Informally, sequential consistency implies that operations appear to take place in some total order and that that order is consistent with the order of operations on each process.
Sequential consistency cannot provide guarantees of ordering across processes
Any value for reads is accepted, very weak gaurentee.
Any commited value for reads are accepted, slightly stronger than read Uncommitted.
Both read committed and Uncommitted dont mention anything about recency gaurenteed, make use of that property for solving challenges