section 1

 

 

 

hp storage white paper

 

gives 100X the data protection of traditional

environment changes. HP’s Virtual Array

RAID 5 and 10X the data protection of RAID 1.

Architecture tunes the array automatically, 24

Second: The HP Virtual Array stripes across all

hours per day. It is the hands-down winner in

the disks in the redundancy group. This involves

real-world performance. A better analogy1would

more disks but is not so different from any other

be to compare the multiple manual processes

RAID 1+0 implementation. Third: array striping

required to set the type, load the paper, and

is the way of the future. It’s faster and safer.

actually print books on the old-style printing

 

 

 

 

presses with those of the automated printing

Question: Doesn’t all this “behind the scenes”

systems of our generation. Obviously, automation

movement of data require a huge performance

in printing presses adds to greater performance.

hit? Surely, the trade-off for virtual technology is

It works the same for arrays.

slow performance.

 

 

Question: Wouldn't striping the data across

Answer: Not true. For years, HP’s original

such large RAID groups make the disk rebuild

virtual array,

the AutoRAID

Model 12H,

was

times very long and take up a high percentage

used for HP’s

V-class TPC-C

benchmark

tests.

of the array resources?

And today, HP Virtual Array products have been

Answer: Because of HP’s RAID 5DP this is

used for the new rp8400 benchmark testing and

are scheduled to be used for the Superdome

practically a non-issue for HP Virtual Array

TPC-C tests. Remember, the HP Virtual Array

products. The HP Virtual Array’s RAID 5DP gives

mimics the policies of experienced system

each redundancy group 10x the protection of

administrators. Would an experienced system

RAID 1. RAID 5DP requires that 3 drives would

administrator do a reconfiguration of the array

have to fail before there would be data loss.

during a period of high workloads? No! And

Thus, even AFTER a drive fails, the data is STILL

neither would the HP Virtual Array. The HP Virtual

protected with the same degree of protection as

Array policy is to NOT perform the background

standard RAID 5. Finally, this means that a single

tuning operations when the array is under a

drive failure does not put the data at risk and

greater than 60% workload.

 

 

therefore does not require an emergency

 

 

 

 

rebuild. The HP Virtual Array can take the time

Question: Isn’t manual always better than

and do the rebuild in the background without

automatic? In cars, manual transmissions give

impacting incoming I/Os. Also, the HP Virtual

better performance than automatic transmissions

Array will rebuild the RAID 1+0 data first since

because they give the driver more control over

that is the most vulnerable after a failure. In all

performance; likewise wouldn’t manual RAID

cases, data integrity is ensured and performance

configurations be better than HP’s Virtual Array

is preserved. No other array can make this claim.

Technology and its automatic RAID configurations?

Question: If your environment is totally stable,

Answer: Manual transmissions in cars would

wouldn’t a manual configuration by an experienced

not give better performance if drivers were only

system administrator result in better performance

allowed to shift gears once

and could never

than one derived from the virtual array’s policies?

change them after that. In essence, this is what

Answer: Let’s first admit it: Totally stable

you have with traditional disk arrays. You are stuck

with the initial configuration unless you bring the

environments are rare. But the answer is that if

array down and go through a time-consuming

the environment were totally stable, and if the

and complex

reconfiguration every time the

administrator configured the array absolutely

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