midpoint / fortuna-oj-doc

Documents of Fortuna Online Judge (Unofficial)

Documents for Fortuna Online Judge (Unofficial)

中文文档

1. How to solve "Failed to write session data" problem?

   fortuna-oj uses redis to handle with session data (and submissions). Usually problem occurs because the AOF file of redis is corrupted, due to accidental reboots of the web server.

   To identify this problem, please check redis log (usually in /var/log/redis/redis-server.log).

   To solve this:

   1. Go to /var/lib/redis in terminal, find "appendonly.aof"

   2. Execute sudo redis-check-aof --fix appendonly.aof to fix the AOF file

   3. Execute sudo service redis-server restart to restart redis background service

   4. Kill php and restart yaujpushd service to reset the submission queue if necessary

      • sudo killall php
      • sudo service yaujpushd start
      • Rejudge all submissions that are pending to be judged in the webpage

2. Some of the submissions are being judged, but way slower than usual.

   fortuna-oj uses vfk_uoj_sandbox for running submissions' programs. Due to an unknown issue (most probably because I'm too garbage :( ), the sandbox will become much slower when judging a specific kind of Pascal programs which have I/O problems (e.g. reading too much data from input).

   Unfortunately there is no way to completely solve this problem. But still, stopping users submitting wrong Pascal programs (especially submitting them repeatedly) might be the best solution.