/participant_data/ too many queries

[metenn]

With 7 models referencing back to the Participant model and no prefetch_related()/select_related(), participants_data view produces a ton of queries, which is slow.

[otargowski]

Is comprehensively optimizing oioioi in the area of db queries planned for the near future (this semester)?
If so, then I have some patches, which greatly improve the performance for the some of the basic views for contests with a lot of problems (let's say 30+, but 100+ was the target).
Iirc, most of those are trivial (@request_cached or select/prefetch_related).

[MasloMaslane]

Recently, we (as in OI's tech team) started looking into improving the performance of oioioi. We'd be very grateful if you would like to share your patches with us!