A storage array consists of a large number of disk drives together with a storage controller. Many servers can be connected to a storage array, which allows any of the disk drives to be used by any server. Data is read from the disk and written to the disk with a read/write heads (Figure 1). The disk spins at between 7,200rpm and 15,000rpm. The heads are moved across the recording surface of the disk to different tracks where the data is stored.

1. Wikibon Green Validation Report Wikibon Energy Lab
Nexsan Energy Efficient
AutoMAID Technology
September 2009
Wikibon.org

2. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Contents
• 1.0 Introduction
• 2.0 Executive Summary
• 3.0 Technical Overview
• 4.0 Measurement Methodology for power.
• 5.0 Drive & Controller Measurement Results
• 6.0 AutoMAID Effectiveness in the Real World
• 7.0 Appendix I – Benchmark I/O Definition
• 8.0 Appendix II Detailed Measurements (VA)
• 9.0 Appendix III – Description of Wikibon Energy Lab Power Calculator for
AutoMAID
• 10.0 Appendix IV Description of Nexsan AutoMAID
1.0 Introduction
Wikibon Energy Lab Validation Reports are designed to assist customers in
understanding the degree to which a product contributes to energy efficiency. The four
main goals of these studies are to:
1. Validate the hardware energy efficiency of a particular technology as compared to
an established baseline.
2. Asses the potential contribution of software technologies to power savings, and
validate the actual contribution in real world installations.
3. Quantify the contribution of the hardware and software technologies to a green
data center.
4. Educate business, technology, and utility industry professionals on the impact of
technologies on reducing energy consumption.
Our objective is to identify not only the hardware energy consumption but also the often
overlooked and hard-to-quantify green software aspects of technologies. Wikibon Energy
Lab Validation Reports are submitted to utilities such as Pacific Gas & Electric Company
as part of an energy incentive qualification process.
Wikibon Energy Lab defines and validates the hardware testing procedures to determine
the energy consumed by specific products in various configurations. As well, Wikibon
reviews actual customer results achieved in the field to validate the effectiveness of these
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3. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
technologies based on real-world field-data analysis. These proof points are mandatory
for the utility company to qualify a specific vendor's technology for energy incentives.
Wikibon Energy Lab Reports are not sponsored. Rather they are deliverables required by
PG&E and other utilities as part of an incentive qualification process. As part of its
Conserve IT Program, Wikibon is paid by the vendor to perform services associated with
securing incentive rebates from utilities for end customers that acquire the vendor's
technologies. To ensure this process is completely independent, Wikibon lab and field
results are sometimes vetted by a third party engineering firm hired by PG&E or other
utilities.
Wikibon only produces Lab Validation Reports for technologies that have been qualified
for rebate incentives by PG&E or other utilities and have passed strict utility company
guidelines. By adhering to this criterion, Wikibon assures its community of the
independence of these results.
Disclaimer
This report was prepared by Wikibon. Reproduction or distribution of the whole, or any part, of
the contents of this document without written permission of Wikibon is prohibited. Neither
Wikibon nor any of its employees make any warranty or representations, expressed or implied, or
assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any
data, information, method product or process disclosed in this document, or represents that its use
will not infringe any privately-owned rights, including, but not limited to, patents, trademarks, or
copyrights.
Page 3 of 30

4. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
This report uses preliminary information from vendor data and technical references. The report,
by itself, is not intended as a basis for the engineering required to adopt any of the
recommendations. Its intent is to inform the customer of the potential cost savings. The purpose
of the recommendations and calculations is to determine whether measures warrant further
investment of time and/or resources.
2.0 Executive Summary
A storage array consists of a large number of disk drives together with a storage
controller. Many servers can be connected to a storage array, which allows any of the
disk drives to be used by any server. Data is read from the disk and written to the disk
with a read/write heads (see figure 1 below). The disk spins at between 7,200rpm and
15,000rpm. The heads are moved across the recording surface of the disk to different
tracks where the data is stored.
Disk Arm Read/write Head
Disk Platter (1 of 3)
Figure 1 - Components of Disk Drive
In traditional storage arrays all the disks are spinning all the time, even when they were
not reading or writing data (not doing any IO, in computer parlance). About 80% of the
energy consumed by a storage array goes to spinning the disks and moving the read/write
heads.
Nexsan has developed software and hardware features called AutoMAID, a sophisticated
technology to turn off individual drives in an array when they are not being used. There
are 3 levels of AutoMAID. Each level saves more power. When a disk drive goes into
idle state (i.e., no data is being read or written, no IO activity) for 10 minutes, the drive
goes into AutoMAID level 1. After 10 more minutes with no IO activity, it goes into
AutoMAID level 2, and after 10 more minutes into level 3. The delay is added to avoid
“hunting” between AutoMAID levels, which would increase power momentarily when
the disk became active.
Page 4 of 30

5. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Figure 2 below shows power required for idle disks and for each level of AutoMAID.
These figures were determined at Nexsan’s laboratory on Nexsan equipment under the
guidance and supervision of Wikibon Energy Labs. Wikibon certifies the accuracy of the
data.
Average Power Required for Different Levels of AutoMAID
14.0
13.0
Power for Hitachi 1 Terayte Disk Drive (Watts)
12.0 11.5
10.0 9.2
8.0
6.0 5.6
4.0 3.4
2.0
-
Drive Active Idle Disk Drive AutoMAID Level AutoMAID Level AutoMAID Level
(No IO Activity) 1 (15% to 20% 2 (35% to 45% 3 (60% to 70%
power savings) power savings) savings)
Level of AutoMAID
Figure 2 - Power Required for Hitachi 1 Terabyte Disk Drive with Different Levels of AutoMAID
The time that AutoMAID is invoked can be determined by running a standard report from
each Nexsan array that itemizes the percentage of time each level of AutoMAID is used,
as illustrated in Figure 3 below.
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6. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Figure 3 - Report on AutoMAID Performance from a SATABeast Array (Source: Nexsan, 2008)
Wikibon has developed a Wikibon Energy Lab Power Calculator for AutoMAID to
determine the power savings and the rebates. If the data from figure 3 is entered into the
calculator, the savings are shown in Table 1 below. In this example, the savings would by
19,764kWh/year (39%).
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7. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
3.0 Technical Overview
MAID technology was introduced first by Copan. In the Copan MAID storage
technology the maximum number of drives that could be running (spinning) at any given
time was 25% and 75% of all the drives were turned off. This technology is suitable for
workloads that use the drives in the same manner as tape drives such as in backup and
archiving applications. With these applications almost all the I/O activity is sequential;
although there is significant delays for data on an idle disk that is randomly accessed (a
drive has to be powered down and another powered up), the number of these data
accesses are few and the delay can be tolerated by the application and users. However
many if not most applications require the ability to make random access to all data on all
disks, and the COPAN implementation of MAID cannot be applied generally.
Drive manufacturers such as Hitachi have recently introduced multiple powered down
states. This was first introduced for laptops, and has now been extended into enterprise
SATA drives that are used in enterprise storage arrays. For example, Hitachi allows a
drive to be in one of four power states:
Level 0:
o Normal operation at 7,200 rpm with heads loaded (un-parked)
MAID level 1:
o Heads Unloaded (parked, reduces wind resistance on heads)
o 15% to 20% power savings
o Sub-second recovery time
MAID level 2:
o Heads Unloaded,
o Slows to 4000 rpm
o 35% to 45% power savings
o 15 second recovery time
MAID level 3:
o Stops spinning (sleep mode; powered on)
o 60% to 70% savings
o 30 to 45 second recovery time
Seagate has a SATA drive that allows the drive just to be powered off (MAID level 3),
and Western Digital has a SATA drive so-called “Green Drive” that revolves slower
(5,400rpm) and can also park the heads (MAID level 1). Nexsan currently deploy Hitachi
and Seagate drives in their SATA storage arrays, and may introduce other disk
manufactures later.
Nexsan has developed software and hardware features called AutoMAID that allows
control of when these levels are evoked and how quickly, which level of MAID is
invoked, and reports to the user of the amount of time that each of the drives is in each
MAID state.
Page 7 of 30

8. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Wikibon defined and reviewed the power measurements on the drives available on
Nexsan’s SATABeast & SATABoy storage arrays, with and without the use of
AutoMAID. Wikibon found that the key variables that determined the power usage were
the type of controller (SATABeast or SATABoy), the number of controllers (dual or
single) and the level of AutoMAID engaged. Table 2 below gives the savings per drive
from AutoMAID, which were derived from the detailed component measurements taken.
The section below called “Power Measurement Methodology” gives additional detail.
Wikibon and Nexsan conducted a rigorous analysis of the benefits that Nexsan customers
had achieved with the use of AutoMAID. The analysis showed that when AutoMAID is
installed in a suitable environment, the disks will be stopped on average over 50% of the
time. Full details are given in the section “AutoMAID Effectiveness in the Real World”
below. These savings can be verified with a report from each array that itemizes the
savings, as illustrated in Figure 4.
Used in combination, these results represent a complete and accurate reflection of the
actual power that would be consumed by Nexsan’s storage array products in a data center
Page 8 of 30

9. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
environment with and without AutoMAID, and the likely power efficiency savings that
AutoMAID will achieve.
Figure 4 - Report on AutoMAID Power Efficiency from SATABeast/SATABoy Arrays (Source:
Nexsan, 2008)
Wikibon Energy Labs developed the Wikibon Energy Lab Power Calculator for
AutoMAID. The methodology used was based on PG&E methodology for calculating
incentives. The data in this report is used in the calculator. The detailed inputs and
outputs are shown in Appendix III.
Page 9 of 30

10. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
4.0 Measurement Methodology for Power
The Nexsan SATABeast and SATABoy storage arrays are built from standard
components, and enable the power of different configurations to be calculated. The
measurements were made at the component level; measurements were taken of the array
controller (either single or dual) and the drives. Included in the measurements was the
performance of the drives when idle and under a benchmark load, and when different
levels of AutoMAID were invoked. Table 2 above gives the impact of the measurements.
Table 3 below gives power consumption of the key components in the SATABeast and
SATABoy configurations.
The measurements on the array controllers were for AutoMAID level zero (i.e., normal
operation) were made with a mixed workload of sequential reads, random reads,
sequential writes, random writes and idle state (no data being transferred). All the
measurements for AutoMAID levels one through three were made with the system in idle
state.
The results of the three workloads were averaged to produce an overall figure of power
consumption for each of the components of the Nexsan arrays. Wikibon believes that the
benchmarks used and the power measurements made were done professionally and in
good faith. In the opinion of Wikibon, this measurement represents a good and
reasonable estimate of the power consumed in the real world applications across a
number of drives for “typical” combinations of applications found in a data center.
4.1 Equipment Measured
The Nexsan storage array and components measured were:
o SATABeast Dual Controller - GN60
o Controllers - 000402FC400D / 000402FC312B
o Chasis - 01754065
o 512MB cache per controller
o 42 x Drives
o 4 x 10 disk RAID 5 sets
o 1 volume per RAID set
o 2 x Hot spares
o DCNR - one Volume per port or Single controller 2 volumes per port
The load testing host equipment was:
o Dell 1850, Dual 3Ghz Xeon CPU
o 2 x Q-Logic 8GBp/s Dual port HBA's
o 4 or 2 ports Direct Attached in dual controller or single controller respectively
The drives measured were:
o Hitachi HUA721010KLA330 7200rpm 1TB, 750GB, 500GB SATA drives
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11. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
o Seagate ST31000340NS 7200rpm 1TB, 750GB SATA drives
o Western Digital WD1000FYPS 5400rpm 1TB (not included in results as not yet
announced by Nexsan)
4.2 Measuring Equipment Used
Amp measurements were made with a Fluke 600 A AC True-rms Clamp Meter 335, SN –
95980112. Volt measurements were made with a Fluke 189 True-rms Multimeter.
4.3 Location of Testing
The testing was done in Nexsan’s facility at Application Support Lab 1, Nexsan
Technologies, 302 Enterprise Street, Escondido, CA 92029 USA (tel: 866.463.9726). The
testing was overseen by Nitsan Tucker, at the above address and phone number.
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12. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
5.0 Drive & Controller Measurement Results
The chart below summarizes the power consumption results from the drive and controller
measurements taken by Nexsan. The detailed measurements are shown in Appendix II.
The results of the analysis allow the power consumption of each of the drive components
(drive chassis and each disk drive type) to be calculated. The final results are shown in
Table 3. This table is used to power the incentive calculator for AutoMAID.
The characteristics of the
benchmarks run to give the
measurements under load are
given in Appendix I below.
The controller and drive figures
under load were used to
determine the power
consumption that would have
been required without AutoMAID, the base case. The idle drive figures were used to
calculate the reduction of power requirements as a result of AutoMAID, and calculate the
overall power consumption with AutoMAID. The difference between the two gives the
direct drive power savings. Derived from AutoMAID.
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13. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
6.0 AutoMAID Effectiveness in the Real World
Nexsan did a detailed study of eight customers who were analyzing the deployment of
AutoMAID across multiple SATABeast arrays. The results of the study are shown in
Table 4 below. What was interesting was the high variability of when AutoMAID could
be deployed. The most interesting statistic was that AutoMAID could be deployed at
some level 58% of the time. The other interesting statistic was that 80% of the time that
AutoMAID was deployed, it was deployed at level 3, the highest level of power saving.
Nexsan Storage Use MAID Levels
User Application Day Evening Weekend Comments AM0 AM1 AM2 AM3
Most clients use the system during
Genealogy Data 1 2 4 the evening and weekends ‐ day 48% 5% 5% 43%
use is light
Medical Image Archive 4 1 2 52% 4% 4% 39%
Scientific Images 1 2 2 31% 6% 6% 57%
email Archive 1 2 2 31% 6% 6% 57%
Medical Research Archive 2 2 3 46% 6% 6% 43%
Test System for delivering rich media 2 2 3 46% 6% 6% 43%
Test System for delivering scientific research data 2 2 3 46% 6% 6% 43%
Part of the system is used for
Storage and backup of rich media 3 2 1 backup ‐ that portion can use MAID 40% 6% 6% 48%
since day use is light
Hours/week 60 60 48 Average 42% 6% 6% 47%
AutoMAID Profile MAID Level AM0 AM1 AM2 AM3
High (AM0 14%, AM1 7%, AM2 7%, AM3 72%) 1 High 14% 7% 7% 72%
Average (AM0 40%, AM1 6%, AM2 6%, AM3 48%) 2 Average 40% 6% 6% 48%
Low (AM0 60%, AM1 5%, AM2 5%, AM3 30%) 3 Low 60% 5% 5% 30%
None (AM0 100%, AM1 0%, AM2 0%, AM3 0%) 4 None 100% 0% 0% 0%
Table 4 - Study of Nexsan SATABeast Storage Users and deployment of AutoMAID
The following screen shots of the AutoMAID Utilization Tracking Log Screen were
taken from eleven (11) production Nexsan SATABeasts and SATABoys with AutoMAID
installed. They show the level of impact on energy efficiency that AutoMAID has had on
these arrays. The results vary from very little impact to very high impact.
Figure 7 shows the log from a 42TB (42 disk) SATABeast system used for running
various test in a LB. The 90 day log shows high energy saving, with the disks stopped
85% of the time.
Page 13 of 30

14. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Figure 5 -SATABeast System 42TB used for running various tests in a LAB – High Energy Saving –
90 day log
The array reflected in Table 5 was being used in a test environment. Over a 45 day period
the disks in the system were stopped (AutoMAID level 3) 96% of the time. This is
characteristic of many test environments, with long inactivity and occasional bursts of
critical work.
Table 5- SATABeast 42TB System used for running customer application simulations in a LAB –
High Energy Saving – 45 day log
The report from the array in Table 6 shows a smaller high-end production environment
with critical databases where AutoMAID was not relevant. The disks were active 93% of
the time, and the energy savings from AutoMAID were low to negligible.
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15. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Table 6 - 4TB System used in high end production environment with critical databases – Low Energy
Saving – 30 day log
The array log in Table 7 shows the power saving results from a file and image content
system for long-term archiving. AutoMAID is highly relevant. The disks were stopped
89% of the time, and the energy savings from AutoMAID were high.
Table 7 - SATABeast 42TB System used for holding file and image content for long term– High
Energy Saving – 120 day log
The array log in Table 8 shows the power saving results from a small company mixed
application environment with a mix of very active and non-active systems. file and image
content system for long-term archiving. AutoMAID is highly relevant. The disks were
stopped 30% of the time, and the energy savings from AutoMAID were medium to low.
Table 8 - 14TB System used in daily production environment for a small company with a mixed
application environment - Medium to Low Energy Saving – 60 day log
The array log in Table 9 shows the power saving results from an archiving system.
Again, AutoMAID is highly relevant. The disks were stopped 85% of the time, and the
energy savings from AutoMAID were very high.
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16. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Table 9 - SATABoy 14TB System used for holding archive data– High Energy Saving – 50 day log
The array log in Table 10 shows the power saving results from a backup and recovery
system for a full production environment. This type of system is characterized by very
significant activity for short periods of time, followed by inactivity for most of the time.
This is an excellent environment for AutoMAID, and the disks were stopped 81% of the
time. The energy savings from AutoMAID were very high.
Table 10 - SATABeast 42TB System used in backup environment- holding backups of production
environments – High Energy Saving – 65 day log
The array from the log in Table 11 shows the power saving results from a system
designed to test video games systems. This and other resting environments are excellent
for AutoMAID, and the disks were stopped 90% of the time. The energy savings from
AutoMAID were very high.
Page 16 of 30

17. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Table 11 - SATABoy 14TB System used for testing video systems– High Energy Saving – 75 day log
The array from the log in Table 9 shows the power saving results from a system newly
installed and at rest. This happens a lot, before systems are migrated over to the new
system. This of course reduces the power consumption very considerable and is a tailor-
made environments for AutoMAID with the disks stopped 99% of the time. The energy
savings from AutoMAID were very high.
Page 17 of 30

18. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Table 12 - SATABoy 14TB System at rest – powered but not being used – High Energy Saving – 2
week log
The array from the log in Table 13 shows the power saving results from a long-term
content archiving system. As usual, this is a suitable environments for AutoMAID with
the disks stopped 94% of the time. The energy savings from AutoMAID were very high.
Page 18 of 30

19. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Table 13 - SATABoy 14TB System used for holding content for long term– High Energy Saving – 50
day log
The array from the log in Table 14 below shows the power saving results from a testing
and simulation environment. This again is a suitable environments for AutoMAID with
the disks stopped 81% of the time. The energy savings from AutoMAID were high.
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20. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Table 14 - SASBoy 4TB System used for testing and simulations– High Energy Saving – 40 day log
Overall the percentage of time that AutoMAID was able to save power by stopping the
disks varied from 3% to 99%. The majority of the environments were well over 50%.
In some environments there will be software constraints that will mean that AutoMAID
levels 3 and sometimes 2 cannot be deployed. Almost all environments should be able to
take advantage of AutoMAID level 1.
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21. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
7.0 Appendix I – Benchmark I/O Definition
The definition of the I/O loads that were run against the components is given in Table 15
below. The average I/O block size is 1 MB, which is a reasonable estimate of what is
found in real-world usage of Nexsan SATABeast and SATABoy storage array
deployments. This benchmark was run against all the array components and the power
measurement (volts and amps) were taken. All the array components were also run in idle
state, i.e., no I/O.
The overall mix for components load was defined as 2/3 load benchmark (as defined in
Table 15 above), and 1/3 idle measurements. Wikibon confirms that this is an accurate
estimate of the power consumption that would be found in real world conditions when
under load.
Page 21 of 30

22. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
8.0 Appendix II – Detailed Measurements (VA)
Page 22 of 30

23. Single Single Single Single
Peak without Idle without Load without Emply 2/2 Emply 2/2 Drive Single Single Single Drive Drive Drive Drive
MFR MFR M/N CAPACITY/RPM Test Peak Idle Load Chassis Chassis Chassis MAID Lv1 MAID Lv2 MAID Lv3 # Drives chassis Peak chassis Idle Peak Drive Idle Drive Load Average MAID Lv1 MAID Lv2 MAID Lv3
Hitachi HUA721010KLA330 1000/7200 Amps 9 6.1 6.9 9 6.1 6.9 5.3 3.9 3.1 42
Hitachi HUA721010KLA330 1000/7200 Volts 114.3 115.15 115.65 114.3 115.15 115.65 114.8 116.73 116.95 42
Hitachi HUA721010KLA330 1000/7200 Watts 1028.7 702.415 797.985 808.68 482.395 577.965 388.42 235.227 142.525 42 220.02 220.02 19.3 11.5 13.8 13.0 9.2 5.6 3.4
Hitachi HUA721010KLA330 1000/7200 BTU/hr
Hitachi 750/7200 Amps 8.6 5.6 6.9 9 5.6 6.9 5.3 3.9 3.1 42
Hitachi 750/7200 Volts 116.9 117.3 115.65 114.3 117.3 115.65 114.8 116.73 116.95 42
Hitachi 750/7200 Watts 1005.34 656.88 797.985 808.68 436.86 577.965 388.42 235.227 142.525 42 220.02 220.02 19.3 10.4 13.8 12.6 8.4 5.1 3.1
Hitachi 750/7200 BTU/hr
Wikibon Energy Lab
Hitachi 500/7200 Amps 8.1 4.9 6.9 9 4.9 6.9 5.3 3.9 3.1 42
Hitachi 500/7200 Volts 116.94 117.2 115.65 114.3 117.2 115.65 114.8 116.73 116.95 42
Hitachi 500/7200 Watts 947.214 574.28 797.985 808.68 354.26 577.965 388.42 235.227 142.525 42 220.02 220.02 19.3 8.4 13.8 12.0 6.8 4.1 2.5
Hitachi 500/7200 BTU/hr
Seagate ST31000340NS 1000/7200 Amps 9.7 5.5 6.7 9.7 5.5 6.7 x x 2.7 42
Seagate ST31000340NS 1000/7200 Volts 114.2 115.2 115.1 114.2 115.2 115.1 x x 116.1 42
Seagate ST31000340NS 1000/7200 Watts 1107.74 633.6 771.17 887.72 413.58 551.15 x x 93.45 42 220.02 220.02 21.1 9.8 13.1 12.0 9.8 9.8 2.2
Seagate ST31000340NS 1000/7200 BTU/hr x x
Seagate 750/7200 Amps 8.8 5.3 6.7 9.7 5.3 6.7 x x 2.7 42
Seagate 750/7200 Volts 114.81 115.05 115.1 114.2 115.05 115.1 x x 116.1 42
Seagate 750/7200 Watts 1010.328 609.765 771.17 887.72 389.745 551.15 x x 93.45 42 220.02 220.02 21.1 9.3 13.1 11.8 9.3 9.3 2.2
Seagate 750/7200 BTU/hr x x
Nexsan Storage Arrays with
Page 23 of 30
AutoMAID Technology

24. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
9.0 Appendix III – Description of Wikibon Energy
Lab Power Calculator for AutoMAID
The information for the Nexsan customer applying for the PG&E incentive is input in the
blue boxes as illustrated in Figure 8 below.
Step 1 - Customer Information
Company Name: Nexsan Customer
Street Address: 1 Data Center Blvd.,
City: City
State: CA
Zip Code: 94000
Figure 6 - Wikibon Energy Lab Power Calculator Input - Customer Information
The equipment that will be installed is input in the blue boxes as illustrated in Figure 9
below.
Step 2 - Storage System Information
Proposed Storage System - Enter the description, drive size, and number of drives for the proposed storage systems.
Inputs
Total Storage
Description System for Nexsan SATABeast Vendor Drive Size # Disk Drives
Capacity
GB # TB
Storage System Requirements Hitachi 500 0 0
Storage System Requirements Hitachi 750 0 0
Storage System Requirements Seagate 750 0 0
Storage System Requirements Hitachi 1000 200 200
Total Storage 200 200
SATABeast
Number of SATA Beasts 5
Dual or Single Controller? Dual
Total Storage
Drive Size # Disk Drives
Description System for Nexsan SATABoy Capacity
GB # TB
Storage System Requirements Hitachi 500 0 0
Storage System Requirements Hitachi 750 0 0
Storage System Requirements Seagate 750 0 0
Storage System Requirements Hitachi 1000 0 0
Total Storage 0 0
SATABoy
Number of SATABoys 0
Dual or Single Controller? Single
The proposed storage system with AutoMAID provides the same performance as the baseline storage system with fewer number of drives spinning and
Assumptions: lower power costs
Figure 7 - Wikibon Energy Lab Power Calculator Input - Storage System Information
The information about UPS in the data center where the storage equipment will be
installed is input in the blue boxes as illustrated in Figure 10 below.
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25. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Step 3 - UPS Information
Units Comments
UPS present in data center? Yes If yes, UPS losses included in cooling load calculations
Total UPS Capacity 250,000 VA Enter total rated UPS capacity
Baseline UPS Loading 100,000 VA Connected critical load using standard storage system, incl
UPS type (see table below) 1 Use Type 1 if unsure
UPS Efficiency Profiles
Label Description Comments
1 Baseline UPS efficiency Equivalent to average double conversion performance
2 High Efficiency Double Conversion Best measured efficiency curve for double-conversion UPS.
3 High Efficiency Delta Conversion Measured efficiency for delta conversion line-interactive UPS.
4 High Efficiency Flywheel Based on 4th order polynomial best fit of flywheel data.
5 User Defined Efficiency Curve If known, enter efficiency of UPS on Calculator tab
Figure 8 - Wikibon Energy Lab Power Calculator Input - UPS Information
The information about the cooling in the data center where the storage equipment will be
installed is input in the blue boxes as illustrated in Figure 11 below.
Step 4- Cooling System Information
Existing Cooling System Capacity 2 Enter single-digit number from Table below.
Cooling System Types
Worst
Efficiency
Individual
Nominal During
Compressor Annual Average
System Installed Cooling Summer
Baseline Cooling System Nominal Efficiency
Type Capacity Peak
Capacity
Demand
Period
tons* tons kW/ton kW/ton
1 < 360 Air-cooled DX CRAC units 40 1.29 1.64
2 >= 360 Water-cooled chilled water plant, serving chilled water CRAC units <150 1.22 1.22
3 >=150 and 1.13 1.13
<300
4 >=300 1.01 1.01
5 n/a No dedicated computer cooling 0 0 0
* Not including redundancy. 1 ton of cooling is equal to 3.52 kW. For 100 kW of energy input to the storage system, 28.4 tons of cooling is required.
Figure 9 - Wikibon Energy Lab Power Calculator Input - Cooling System Information
The information about the AutoMAID usage on the storage equipment will be installed is
input in the blue boxes as illustrated in Figure 12 below. On initial submission, the usage
is estimated using the pull-downs for daytime, evening and weekend AutoMAID usage.
When the storage system is installed, the data from the AutoMAID Performance report
(see Figure 3 for an example) can be input.
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26. Wikibon Energy Lab Nexsan Storage Arrays with
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Step 5 - Other Customer Inputs
Annual Average Electric Cost $ 0.12 per kWh Including all fees and demand charges.
Cost of AutoMAID per SATABeast Controller $ 10,000
Cost of AutoMAID per SATABoy Controller $ 5,000
Total Cost of Storage System with AutoMAID $ 300,000 Note: The total cost includes the software costs
Total Cost of AutoMAID Features $ 50,000
Total Cost of Storage System without AutoMAID $ 250,000 This is calculated by taking the total cost of the Storage system with software and subtracting the cost of the software
Type of AutoMAID Profile Daytime Low (Active 45%, AM0 11%, AM1 7%, AM2 7%, AM3 30%)
Type of AutoMAID Profile Evening High (Active 5%, AM0 3%, AM1 7%, AM2 0%, AM3 85%)
Type of AutoMAID Profile Weekend High (Active 5%, AM0 3%, AM1 7%, AM2 0%, AM3 85%)
AutoMAID Profile Active AM0 (Idle) AM1 AM2 AM3
High (Active 5%, AM0 3%, AM1 7%, AM2 0%, AM3 85%) High 5% 3% 7% 0% 85%
Average (Active 25%, AM0 15%, AM1 6%, AM2 6%, AM3 48%) Average 25% 15% 6% 6% 48%
Low (Active 45%, AM0 11%, AM1 7%, AM2 7%, AM3 30%) Low 45% 11% 7% 7% 30%
None (Active 65%, AM0 35%, AM1 0%, AM2 0%, AM3 0%) None 65% 35% 0% 0% 0%
Calculation of Average
AM0=AutoMAID level 0, Idle, no savings Index Hours/Week Active AM0 AM1 AM2 AM3
AM1=AutoMAID level 1, Heads parked 3 60 45% 11% 7% 7% 30%
AM2=AutoMAID level 2, Heads parked and drive slowed 1 60 5% 3% 7% 0% 85%
AM3=AutoMAID level 3, Drive in Standby 1 48 5% 3% 7% 0% 85%
Total 168 19% 6% 7% 3% 65%
Figure 10 - Wikibon Energy Lab Power Calculator Input - AutoMAID Usage Information
The output from the Wikibon Energy Lab Power Calculator is illustrated in Figure 13
below. A more complete read out is available from the Power Calculator is available
when calculating specific incentive amounts.
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27. Wikibon Energy Lab Nexsan Storage Arrays with
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10. Appendix IV – Description of Nexsan
AutoMAID
In tradition storage arrays, disk drives continue to rotate all the time, which uses power
and require cooling. High performance FC disks rotate at 10,000 or 15,000 rpm. Almost
all high density disks (SATA disks) rotate at 7,200 rpm. Nexsan's AutoMAID (Automatic
Massive Array of Idle Disks) energy saving technology transparently places SATA disk
drives into different idle states to reduce power and cooling costs.
AutoMAID is granular to an individual drive or RAID set and offers multiple levels of
energy savings. AutoMAID is user selectable enabling users to determine the right trade-
off between response time performance and energy savings.
Drive manufacturers have recently introduced multiple powered down states. This was
first introduced for laptops, and has now been extended into enterprise SATA drives that
are used in enterprise storage arrays. For example, Hitachi allows a drive to be in one of
four power states:
Level 0:
o Normal operation at 7,200 rpm with heads loaded (un-parked)
MAID level 1:
o Heads Unloaded (parked, reduces wind resistance on heads)
o 15% to 20% power savings
o Sub-second recovery time
MAID level 2:
o Heads Unloaded,
o Slows to 4000 rpm
o 35% to 45% power savings
o 15 second recovery time
MAID level 3:
o Stops spinning (sleep mode; powered on)
o 60% to 70% savings
o 30 to 45 second recovery time
Seagate has a SATA drive that allows the drive just to be powered off (MAID level 3),
and Western Digital has a SATA drive so-called “Green Drive” that revolves slower
(5,400rpm) and can also park the heads (MAID level 1). Nexsan currently deploy Hitachi
500GB, 750GB and 1TB drives, together with 750GB Seagate drives in their SATA
storage arrays, and may introduce other disk manufacturers later.
It is expected that drive manufactures will introduce additional levels of power savings,
and much faster recovery times to access data. The faster recovery times will be
particularly useful, as it will avoid potential impacts on the application.
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28. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Figure 14 below illustrates the cycle of moving from a disk or disks in sleep mode,
through a request for data and reactivation of the drives, through the cascade down
through the MAID levels until the disk is in sleep mode again.
Nexsan storage drives climb to Requests for
full high speed and start data have
managing data requests stopped –
Nexsan * Delay times between moving to
This initial start time varies. AutoMAID different AutoMAID levels and
From MAID level 1 under 1 sec waits another which levels to use are fully
Initial From MAID level 2 15 sec 10* minutes After 10* configurable
From MAID level 3 30-45 sec to be sure minutes
data
there are no Nexsan
request AutoMAID
Note: Many applications / HBAs additional
arrives parks the
have a timeout of 120 sec. Some requests
applications will assume that heads to 10* minutes
there is a I/O problem and evoke conserve later Nexsan
error recovery energy AutoMAID
MAID level 1 slows the
drives to
conserve 10* minutes later
Nexsan storage drives more energy Nexsan AutoMAID puts
are at rest to save MAID level 2 the drives back to rest
energy for maximum energy
MAID level 3 conservation
15-20 % 35-45% MAID level 3
energy energy 60-75% energy
60% energy saving saving saving saving
Figure 11 - AutoMAID in Action (Source: Nexsan, modified by Wikibon)
10.1 Nexsan Storage Array Specifications
SATABeast Technical Specifications
o Up to 42 SATA drives in a 4U rack configuration
o Dual 4Gb Fibre Channel SFP LC host ports per controller
o Dual iSCSI ports per controller
o Single or Dual active/active controllers
o Dual Power Supplies
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29. Wikibon Energy Lab Nexsan Storage Arrays with
AutoMAID Technology
Figure 12 - Nexsan SATABeast (Source: Nexsan, http://www.nexsan.com/satabeast/tech.php,
downloaded 9/28/2008)
SATABoy Technical Specifications
o Dual 2Gb Fibre Channel ports and dual iSCSI ports per controller or quad SCSI
ports on a single controller
o Single or dual active/active controllers
o Up to fourteen SATA drives in a 3U rack configuration
o Dual Power Supplies
Figure 13 - Nexsan SATABoy (Source: Nexsan, http://www.nexsan.com/sataboy/tech.php,
downloaded 9/28/2008)
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30. Wikibon Energy Lab Nexsan Storage Arrays with
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