[keycloak-user] Long user upload procedure

Asking for your help. We start docker image stand-alone Keycloack in openshift. We add new users using REST. But everything works very slowly. For 240000 users the uploads takes 24 hours. 1. Has anyone come across this? 2. How do you add and update users? Our server: CPU 4 4 GB. Our version of keyclock 7.3.1.GA. Thank you Igor