Performance problem - Pages are too slow to load

Codabench is too slow to load.

• Home page of competitions are loading everything at once. We need a lazy loading.

• When a loading is long, it is decreasing the performance for everybody else (this is normal I guess).

• Competitions list is slow to load too, despite the small logos (#1290 (closed)). Code of this page: https://github.com/codalab/codabench/blob/f83f94c1e492da524fef5b2f6ccf26846fa88b69/src/static/riot/competitions/public-list.tag

TODO

• Increase the CPU and RAM of the main VM
• Increase the CPU and RAM of the main VM (again)
• Competition page
  • Trying to remove "entries" column from leaderboard, which may be the one that is slow to load (#1673)
  • Put back "entries" in an efficient way
  • Pagination for "Submissions" tab (and lazy loading)
  • "Show more" on leaderboard results tab. By default show 30 rows, and add more when clicking on show more. If the participants is not on the first 30, it could still be shown at the bottom of the table after some "[...]" row
• Competition list
  • Optimize the code for loading the competitions list (@bbearce) (#1376) (#1381)
  • #1381 improves the query by directly filter public competitions. We need to improve the filter to take into account the dates and page of the public list we are displaying.
• General performance and home page
  • Remove temporarily participants and submissions counters to accelerate the competition loading #1645
  • Participants and submissions counters in an efficient way (#1669)
  • Featured competitions manually set (#1678)
  • Home page counters (#1699)
    • Update the counts somewhere in a file or in the db with a script that is run once a day
    • Update home page to fetch the counts from the file/db to make them dynamic instead of hardcoded