[Info-vax] INIT/LIMIT, SET VOLUME/LIMIT, /MAXIMUM_FILES, /CLUSTER_SIZE

[Phillip Helbig---undress to reply]

Over the past few days, I have initialised various disks, all but one
with a cluster size of 16 (the exception has 128).  They are either 4.3
or 8.6 GB in size.  I compared the value of maximum files as reported by
SHOW DEVICE with that calculated from the formula given in
HELP/INIT/MAXIMUM_FILES:

$ WRITE SYS$OUTPUT f$getdvi(x,"maxblock")/((f$getdvi(x,"cluster")+1)*2), -
   "   ", f$getdvi(x,"maxfiles") 

In some cases they agree; so far, so good.  In other cases, the second 
value is equal to one more than twice the first value.

First question: why the difference?

Second question: could there be some (undocumented) difference between 
INIT/LIMIT and SET VOLUME/LIMIT?

Third question: According to help, the highest possible value of
MAXIMUM_FILES is twice the default value; why do I get, in some cases, 
one more?  (I didn't use the undocumented INIT/SPINAL_TAP.)

Note that I never used the /MAXIMUM_FILES qualifier.