An White paper commisioned by HP for the P4000 (left hand) SAN

http://www.scribd.com/doc/57020729/4AA2-7788ENW



Value of Adding Nodes Online via Storage Clustering
Eighty percent of the users interviewed were actively using this ability with extremely good—and impressive—results that garnered much positive commentary:
 “Prior to the P4000, this took 3-4 days of effort, now it’s just 2 minutes (this happens 4-5 times per year).”
 “We had 2 FTEs before—so this alone saves us one of those and contributes probably $100,000 in cost savings in terms of the uptime; not to mention the 60 or so hours of administration time saved. Our prior approach took at least a month to upgrade, plus overtime, plus downtime … and we were managing a far smaller capacity than now.”
 A slightly more conservative user employs the feature, but “only after-hours, to be ultra safe;” it used to take 4 hours before the P4000 and now takes “minutes.”
 Although only done twice in four years, the approach without the P4000 capability took three weekends of 1 FTE to migrate 5 TB (11 volumes) “and of course, that was just moving the data; the device would be down.” Now it “can be migrated in minutes with a simple point and click—it’s never offline and there’s no overtime.”
White Paper: Business and Operational Benefits Achieved with HP P4000 SANs 9
© 2010, Enterprise Strategy Group, Inc. All Rights Reserved.
 “Before it took at least a day and now it’s minutes.”
 One user spoke of the social convenience (staff “not having to pull all-nighters”) and “extreme confidence” with the online upgrades; saving the overtime was nice, but the improved reliability for customers was excellent. The user also pointed out that the online upgrade saved not just the time of the upgrade itself, but also the three or four days of planning it used to need beforehand.



Value of Thin Provisioning
The use of thin provisioning fell into two distinct camps:
1) Those few users that either barely or did not use thin provisioning at all.
a. One user said it was “not comfortable” and “feels that it’s even less management effort to not try to use it.”
2) The majority, however, do use thin provisioning extensively; on average for around 80% of their volumes. Some examples of individual experiences are:
a. Saving 25% capacity (lower than might be expected because they used to manually over-provision in any case).
b. Saves or reclaims about 40% of capacity; while readers will need to figure their own dollar value, for this user it equated to $50-60,000 per annum.
c. Two users estimated saving a week’s worth of FTE time per year.
d. Saving 50% capacity through reclamation and deferring purchases, said one user, while another estimated 30-40% savings.
e. “Really easy and really quick” was the succinct summary from one customer.