on our Moodle 3.9.3+, running on CentOS 7 Linux, with php 7.2.33 we installed STACK 4.3.7 question with Maxima and use the default setting - see attached STACK-setting.pdf.
However, the performance of STACK question is very slow. On top of it, the STACK heathcheck - see "STACK helthcheck.pdf" - shows plenty of warning.
I tried to speed up Maxima (https://eformation.univ-grenoble-alpes.fr/question/type/stack/doc/doc.php/CAS/Optimising_Maxima.md ) for SBCL, but this gave me errors in Healthcheck.
Any help please, what STACK/Maxima parameters must be changed to have good performance ?