Okay, I've resolved everything. First, the reason why I'm getting the 'pthread_setschedparam failed' error when I run Pharo under Debian is because it must be run as 'root'! Don't ask me why, but that's the reason why Pharo can't set thread priorities. (This wasn't an issue under Ubuntu Server – go figure.)
Second, I am now using Pharo's own SHA256 class. It's probably not as secure (because it doesn't use a salt value) and not as quick to execute (not being C code), but for my purpose, it doesn't really matter. So I can use DigitalOcean or OVH to run my web server in a VPS. -- Sent from: http://forum.world.st/Pharo-Smalltalk-Users-f1310670.html