Difference between Upgraded VMFS 5 and Newly created VMFS 5

This post explains you the major difference between VMFS 5 datastore upgrade from VMFS 3 and  newly created VMFS 5 datastore. VMFS 5 is available as part of vSphere 5. VMFS 5 is introduced with lot of performance enhancements. Newly installed ESXi 5 will be formatted with VMFS 5 version but if you have upgraded the ESX 4 or ESX 4.1 to ESXi 5, then datastore version will be VMFS 3 only. You will able to upgrade the VMFS 3 to VMFS 5 via vSphere client once ESXi upgrade is Complete. Even though the upgraded datastore will be with VMFS 5 version  but there are many technical difference between upgraded VMFS 5 and newly created VMFS 5. This posts tells you some major differences between upgraded VMFS 5 and  newly created VMFS 5.

Upgraded VMFS 5
Newly Created VMFS 5
Max datastore size
64 TB
64 TB
Maximum size of RDM in
Physical Compatibility
64 TB
64 TB
Block Size
Continuous to use the previous block size
which may be 1MB/2MB/4MB/8 MB
only 1 MB block size
Sub-block size
64 KB sub-blocks
8 KB  sub-blocks
File limit
Partition Style
MBR (Master Boot Record) style
GPT (GUID Partition Table)
Partition Sector
 partition starting on sector 128
 partition starting on sector 2,048
Maximum size of RDM in
Virtual Compatibility
2 TB  less 512 bytes
2 TB  less 512 bytes
Max size of file
2 TB  less 512 bytes
2 TB  less 512 bytes