Just wanted to note that one of our AtoM installations was logging "Memory allocation error 1038 Out of sort memory" and returning 500 errors when generating finding aids and looking at the "Manage jobs" page.
We were able to bump the sort_buffer_size to 1048576 bytes (4 times the default) by adding "sort_buffer_size = 1048576" to the mysqld.conf file under the recommend optimizer_switch line. That seems to have fixed the problem.
I'm not recommending this for all AtoM users (I'm a bit fuzzy on what the performance impact of this tweak will be) but if you're experiencing something similar it's at least something to look at.
Carleton University Library