Hi everyone,
we're currently demoing vSAN 6.6 on an all-flash setup. After the upgrade to vSAN 6.6, we have noticed a huge increase in file system overhead.
With dedup & compression enabled, the file system overhead is about 1.7 TB for a 16TB vSAN.
With dedup & compression disabled, the file system overhead is still about 200GB:
Please note that both of these are empty, newly created vSAN datastores containing neither VMs any other objects. In previous releases I've seen file system overhead in the range of a couple of megabytes to maybe a few gigabytes, which also matches the screenshots in the official vSAN 6.6 documentation displaying 11.34 GB file system overhead for a 15TB array.
Is there an explanation for that strange behavior?