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The Question is:
This will be a two-part question about bound VMS disk-sets.
1) After a set of disk have been initialized and bound together by using the
command "MOUNT/SYSTEM/BIND=BLD_TEST DKA0:,DKA100: BLD_TEST_1, BLD_TEST2
BLD_TEST". I then wanted to change the disk labels by using the commands:
"SET VOLUME/LABEL=BLD_DSK_1 DKA
0:" and "SET VOLUME/LABEL=BLD_DSK_2 DKA100:", this worked as expected and
change the disk volume names.
The problem occurs when I want to mount the disk back to the system. By using
the command "MOUNT/SYSTEM/BIND=BLD_DSK DKA0:,DKA100: BLD_DSK_1,BLD_DSK_2
BLD_DSK", I get the fatal error message of: "%MOUNT-F-VOLINSET, volume is
already part of another volum
e set". I have to use the original name of "BLD_TEST" with the /bind command.
How can I change the name given to the "/BIND" command to something different?
2) I ran a benchmark job on a set of newly created bound VMS disk-set and
received a wall time of 1-hour and 10-minutes.
After coping all additional information that is also need on this bound
disk-set and I ran the same benchmark job with the same environment, the wall
time had increased to about 1-hour and 40-minutes. This is an increase of 30
minutes.
The disk that I'm using are "SEAGATE ST336704LC" 35 gb drives in a two-bay
Phoenix PDS100-S2W-2RDR housing.
Why am I getting an increase in my benchmark times?
The Answer is :
The OpenVMS Wizard generally discourages the current and continued
use of bound-volume sets, and would strongly discourage new uses.
The bound-volume set mechanism is an outdated solution to a problem
of insufficient volume capacity, and has various significant drawbacks
in terms of usage, volume management and general operations.
Just one of the possible problems is erratic I/O performance, as the
actual behaviour of a sequence of I/O operations is highly dependent
on the precise state of the members. The OpenVMS Wizard suspects your
benchmark numbers are illustrating this particular side-effect, though
the behaviour could obviously have another trigger.
If you need to combine multiple spindles into a single volume, please
use volume striping (RAID Software for OpenVMS, or other similar
package), or controller-based RAID, or -- far and away the best and
simplest solution -- acquire and configure a larger disk. Again,
the OpenVMS Wizard would not tend to use MOUNT/BIND and the resulting
bound-volume set.
Bound volume sets are not supported as OpenVMS system disks.
For assistance with the performance characteristics and the general
operation of third-party storage, please contact the vendor(s)
supporting the device(s). Related information is available in the
OpenVMS Frequently Asked Questions (FAQ), in the section discussing
third-party peripheral devices.
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