Excessive memory consumption RAID1 ZFS

I have a proxmox 6.4.9 installed in RAID1 ZFS with 40 GB of RAM. On this server 2 VMs are installed, one with 2 GB of RAM and the other with 16 GB of RAM.
Sometimes the VM with 16 GB of RAM is automatically stopped because too much memory is used.
oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0,global_oom,task_memcg=/qemu.slice/102.scope,task=kvm,pid=5311,uid=0

I must have a problem with the ZFS RAID settings. Can you tell me the correct ZFS settings.
Thanks