The Question is:
What performance differences would you expect from moving from Wide SCSI
adapater to UltraSCSI adapters, using RA7000 on an OpenVMS V7.1 Alphaserver
The Answer is :
The performance gain depends highly on what factor(s) are currently
limiting the application performance...
Without specific details on the current application activity and
particularly the current application bottlenecks, the OpenVMS Wizard
could expect anything from zero to very large gains to (rather unlikely,
but still remotely possible) negative performance impact... If the
application is not I/O bound, then there will be little or no gain. If
the application is heavily I/O bound, then improvements in caching and
increases physical memory may be appropriate. If caching is appropriate
and sufficient physical memory is available, then the performance increase
from the storage I/O changes will roughly parallel the differences between
the controller and disk throughput for the subsystems. Obviously...