MongoDB 8.x (both 8.0 and 8.2) uses tcmalloc-google which segfaults
(exit 139) on Hetzner ARM64 kernels with transparent hugepages disabled.
MongoDB 7 LTS uses jemalloc and runs cleanly on the same hardware.
PVC was already wiped so there is no FCV incompatibility.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>