Very Unfair System of Codechef . Lunctime Should be rated

subho57 · January 30, 2021, 7:53pm

I second you broo!!
It should be rated!!

hacking_leo · January 30, 2021, 7:58pm

Absolutely agreed.

shivu_4498 · January 30, 2021, 8:10pm

definitely true

shubhamskk · January 30, 2021, 8:14pm

Agreed.

adarsh08x · January 30, 2021, 8:21pm

Mail them feedback@codechef.com

ashishgup · January 30, 2021, 8:27pm

I have discussed the rationale behind making LTIME unrated here.

The contest was rated until 11:15 pm, but ever since then, the queue kept piling on, and by the time contest ended - solutions submitted at 11:30 did not even have a verdict. How would it be fair for it to be rated?

I’m sorry, I know it sucks and I don’t want any contest to be unrated myself, but in the end - we just faced too many issues at once today, and making it rated would be unfair for all the contestants who suffered.

As you must have read, CodeChef is taking a break from short rated contests until the issues are resolved, so hopefully this is the last time this happens!

TL;DR: Queue issues were the breaking point for the contest - not the server issues.

digon · January 30, 2021, 8:32pm

Thanks for clarifying this

george_ogden · January 30, 2021, 8:39pm

Vote at: Should January Lunchtime be Rated? to display a preference

cubercoder · January 30, 2021, 8:51pm

Was the queue actually a queue?
I noticed that few submissions were randomly not getting a verdict while most others got a verdict.
Even when I myself did not get a verdict for 10 minutes, I made another submission and got a verdict within 1 minute. (all this is after 11:30 btw)

So, if the queue was the same for everyone, can we say the contest was fair?
If for some reason the queue was different for different people, (pardon my limited knowledge of queues but usually I think of FIFO) then I agree we have a problem, but rather than rolling back to cancelling the contest, we might as well consider rolling back to T=11:15 PM since its agreed by the admins that it was the last point where the contest remained fair?

hrsh_panwar · January 30, 2021, 8:57pm

Wut about people who submit all their solutions at the end . Since lunchtime accounts for when the score was achieved this is a valid strategy

akshitm16 · January 30, 2021, 8:58pm

This was something weird. One of my old submissions was in queue for around 10-12 minutes and my latest submission had already got the verdict. When I clicked my old submission, I could see the verdict but it was shown (in queue/running) in my profile.

coder1311 · January 31, 2021, 4:16am

Yes, it should be rated.
This was my first contest on CodeChef and that too announced unrated after the contest.
This is not fair at all, because the problem raised for every participate during the contest.
Please make it rated.

hard_coder2 · January 31, 2021, 4:49am

very true!! I support!

keshavg21 · January 31, 2021, 4:55am

yes they should make the lunctime rated

piyush2552 · January 31, 2021, 5:07am

During the first 30 mins, it is giving the same not found an error again and again but after 30 mins everything is fine. So it is hard to decide whether it should be rated or not because in any case, it’s is unfair to some participants.
At the same time, it is very shameful that CodeChef can not even handle around 6000-7000(approximately) people during a short contest.

anon97292424 · January 31, 2021, 5:56am

So, I think codechef must be using a message queue for their system and you are right about the FIFO but there is not a single instance running on the cloud there are multiple servers(horizontal scaling) now there are load balancers in place for evenly distributing the load so that one server is not significantly ahead of the others(consistent hashing is an algorithm which does that) but as codechef said they are having architecture issues that’s probably the reason why people submitting solutions later getting verdicts faster because the server where there answer went was working while the other server had a long queue or was just down because of the load or any other reason, deducing anything more than this would be speculating for us without knowing how codechefs system works.

cubercoder · January 31, 2021, 6:07am

Good point.
It seems to be more of a problem in the implementation of the queue compared to anything else.
Even at 11:50 P.M, most submissions got a verdict in 1 minute or so. There are few submissions which probably went into queues for a long time while others were judged instantly, this implies that the queue manager/ load balancer was not working correctly (which is even funnier and a bigger architectural problem than just all queues having wait).

If a solution A is in a queue for 10 minutes and other solutions can be judged in one minute, this implies that there is at least one queue with 1 minute wait time, and the solution A should be moved there instead first.

So i suppose its not technically a mere queue load issue(as has happened in the past where some test case was very slow) but more of an architecture/ load balancing/ resilience issue. If we assume the architecture has not changed over the past few months to facilitate this issue, this issue must also have arisen in past contests.
I am still not convinced why single this contest out, unless there is some recent architecture change that caused issues that arose here. If so, i will understand.

shaurya_upd · January 31, 2021, 6:20am

yes it should definitely be made rated.Its really very frustrating and demotivating when you try so hard and finally the contest become unrated.

shubham_chhimp · January 31, 2021, 6:22am

I was thinking about same.
Agree!

seemant0766 · January 31, 2021, 6:23am

exactly…everyone is facing same problem… then why unrated…