[FRIAM] ZFS - Wikipedia, the free encyclopedia

[Marcus G. Daniels]

Robert Howard wrote:
>
> It's a 128-bit file systems, but it has a maximum capacity of 16 
> exabytes, which is 2^64.
>
> I wonder if those additional 64-bits are used to permit client-side 
> random asynchronous GUID identifiers instead of server-side 
> synchronous sequential integers.
>
yow!  I couldn't find an answer (a more motivated person can look 
through the souce code), but I'll throw in another guess:   A 
transaction # + address might hash to a physical location.   That would 
make sense for the transaction model and snapshot system as you could 
find a block from an old version of the file, and would justify why they 
call it a 128-bit filesystem as it would in fact be able to house 
physically that much content...