Found it!
adding
set_lk_max_lockers (not
set_lk_max_locks) did the trick:
set_lk_max_lockers 400000
https://docs.oracle.com/cd/E17276_01/html/api_reference/C/set_lk_max_lockers_parameter.htmlI tested and was able to auto-create and load 932 wallets, until I hit an out of memory error in the db.log:
Logging region out of memory; you may need to increase its size
DB_TXN->abort: log undo failed for LSN: 227 171878: Not enough space
PANIC: Not enough space
PANIC: DB_RUNRECOVERY: Fatal error, run database recovery
PANIC: fatal region error detected; run recovery
Which
set_lg_regionmax 1048576
Can resolve.