1. Does anybody use InnoDB instead of MyISAM with WeBWorK?
2. With no visible initial performance observed between the two could a significant difference show up later with thousands of users and hundreds of courses?
I just installed 2.15 on an ubuntu 20.04.1 on a Microsoft Azur Hyper-V and with both database engines and both with --sync_binlog=0 and 1 the initial OPL-update takes 3 hours. Either there is no significant difference or it is negligible to some other performance issues.
Loading the OPL Directory in the Library Browser takes about 4 seconds either way, and there are no other issues observed so far.
I hesitate to go back to MyISAM from InnoDB.The installation manual mentions "(at least on some hardware) InnoDB seems to be 50-100 times slower than MyISAM". But for example the wikipedia page for MyISAM mentions that "Versions of MySQL 5.5 and greater have switched to the InnoDB engine to ensure referential integrity constraints, and higher concurrency."