[Info-vax] Looking for suggestions for new $GETDVI item codes

[JF Mezei]

On 15-01-15 20:29, Simon Clubley wrote:

> For example, the filesystem needs to know the location of files by
> LBA. You can work around that by using blocklets,

How do other opearting systems handle devices with different physical
block sizes ? Do they use virtual block addresses ?

Then again, if you synthetize 512byte block numbers, you still need to
increase the storage to 64 bits so that at run time, the system can
fully address each virtual block in a very large file.

For the long term, one would want a system that is independent of
physical block size so that as devices evolve, you don't have to fully
rewrite the OS every time.

In the case of RMS indexed files where they use relative file address
for pointers in the index, is that based on assumption of 512byte blocks
? (I forgot how the index pointers to bucktets work, but recall buckets
can be more than 512 bytes)

Obviously, any change at the driver level to support new devices would
have to be transparent to existing RMS indexed files that are just
copied from old system to the new one. (or release notes must specify
that a convert must be done for every indexed file)