qemu with file memory backend.

with file, limit 128 - churn

without file, limit 128 - crash

without file, limit 2 - churn

with file, limit 2 - cache

time qemu-system-x86_64 -accel kvm -snapshot -m 4G -smp 4 Fedora-Cloud-Base-37-1.7.x86_64.raw -nographic -serial mon:stdio -net user -net nic
sysbench memory --memory-block-size=1G --memory-total-size=50G --memory-oper=write --memory-access-mode=rnd --threads=1 run