in queue... what queue?

General topic about Valladolid Online Judge

Moderator: Board moderators

Post Reply
theemathas
New poster
Posts: 19
Joined: Mon Jan 07, 2013 9:30 am

in queue... what queue?

Post by theemathas » Thu Jan 17, 2013 4:37 am

the "in queue" verdict looks strange to me:
  • it is definitely not a "queue" because it's clearly not FIFO
  • it shouldn't be a "priority queue" because there aren't any reasonable priorities
  • it isn't a "queue by received time" because sometimes two consecutive submissions from the same computer (so, different internet connections is out of the question) got judged in the wrong order
  • it shouldn't be anything else since it says "in queue"
then, what queue is it?

lbv
Experienced poster
Posts: 128
Joined: Tue Nov 29, 2011 8:40 am

Re: in queue... what queue?

Post by lbv » Sat Feb 16, 2013 12:54 pm

theemathas wrote:the "in queue" verdict looks strange to me: (..)
then, what queue is it?
An interesting, but kind of strange question... :)

I'm not familiar with UVa's OJ infrastructure to know for sure, but have you considered that it may be a standard queue that is simply serviced by more than one judging server? All submissions arrive to the same queue, and some may go to a slower server, while others go to faster ones.

Or what if it's one multi-threaded server? It might start one judging task in one thread, and if it takes too long, it pauses it, moves to another one, and so on...

Anyway, who knows what really happens behind the curtains, but I just thought that if you want to take the term "queue" so literally, it shouldn't be too hard to come up with a reasonable scenario that explains the behaviour you see.

Post Reply

Return to “General”