The document summarizes performance test results of the IBM LTO-6 tape drive. Key findings include:
1) The LTO-6 tape drive achieves a native data rate of up to 160 MB/s, an increase of 14% over the prior LTO-5 drive.
2) Using new LTO-6 media, the drive provides a native capacity of 2,500GB (6,250GB with 2.5:1 compression), a 67% increase over LTO-5 media.
3) Performance tests show the drive meets or exceeds expectations for data rates when reading and writing both new LTO-6 and prior LTO-5 media formats across a range of compression
IBM System Storage LTO Ultrium 6 Tape Drive Performance White Paper
1. IBM® System Storage®
September, 2012
IBM® System Storage® LTO Ultrium 6 Tape Drive
Performance White Paper
By Rogelio Rivera, Tape Performance
Gustavo Vargas, Tape Performance
Marco Vázquez, Tape Performance
IBM Guadalajara
2. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
Table of Contents
Introduction.....................................1
LTO-6 Tape Drive Overview............1
Performance Overview....................2
Performance Evaluation..................2
FC Data rate Performance..............4
SAS Data Rate Performance..........9
Tape Capacity...............................13
Locate and Rewind Performance..14
Load/Unload Performance............15
Speed Matching Performance......16
Conclusions...................................17
The LTO-6 tape drive features
hardware encryption of data, two
interface options, and two form
factors. The data rate improvement
from the previous generation is 14%
and the tape capacity also increases
67% from the previous generation 5.
Introduction
This white paper describes the performance of the IBM® System Storage® LTO
Ultrium 6 tape drive (LTO-6 tape drive) working on open systems environments.
LTO-6 Tape Drive Overview
The sixth generation IBM LTO-6 tape drive offers a great storage capacity and an
excellent performance using technology designed for the mid range open
systems environment that include IBM System p®, IBM System i® and IBM
System x® servers; selected Oracle® and Hewlett Packard® servers
and Intel® servers running supported versions of Microsoft® Windows®
or Linux®.
There are 2 interfaces available for the LTO-6 tape drive:
• 8Gb Fibre Channel (FC-8)
• 6Gb SAS
Both interfaces are available on half and full heights models.
The IBM LTO-6 tape drive offers a native data rate of up to 160 MB/s an increase
of 14% over the previous IBM LTO-5 tape drive.
The IBM LTO-6 tape drive offers a new generation of data cartridge (gen6 media)
that offers a native capacity of 2500GB (6250GB with 2.5:1 compression) 1.7x the
capacity of the previous gen5 tape cartridge generation. This new capacity is
achieved in the same tape length (846m) as the gen5 media due to a higher
density format (gen6 format).
The IBM LTO-6 tape drive will support the Linear Tape File System (LTFS) which
presents the tape storage as a file-based storage system. Additionally the IBM
LTO-6 tape drive is able to read and write previous generation 5 media
and read only generation 4 media to help customers protect their existing
tape investments.
Page 1
3. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
Performance Overview
The key features of the IBM LTO-6 tape drive are designed to improve
performance and capabilities when compared to the IBM LTO-5, IBM LTO-4 and
other vendors tape drives, some of the improvements are:
• Native data rate of up to 160 MB/s
• Native data physical capacity of 2500GB
• The data compression engine improvements- data that compresses with
LTO-5 drives at 2:1 should now compress at 2.5:1
• Faster tape drive mechanism (9 m/s for half height drives) which results
in quicker locate and rewind times
• Support for 8Gb FC and 6Gb SAS connectivity
• SkipSync Function to provide small file backhitchless flush
capability
• Cache buffer: 1024MB (full height models) and 512MB (half height
models)
This white paper examines the performance benchmarks of the IBM LTO-6 tape
drive and associated features. The performance of the different drive host
interface types will also be closely examined.
Performance Evaluation
All the performance benchmarks were run on one or more of the following
systems:
• Server IBM System x3850 running Linux RHEL 6.1
with an LSI® SAS 9212-4i4e HBA and a QLogic®
QLE2562 8Gb FC HBA.
• Server IBM System x3755 running Linux SUSE 11 SP1
with an LSI® SAS 9200-8e HBA and a QLogic® QLE2562 8Gb
FC HBA.
• Server IBM System x3250 running Linux SUSE 11 SP2 with a
QLogic® QLE2562 8Gb FC HBA.
Page 2
4. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
The performance benchmarks used for the tests are a toolbox of in-
house C-based performance measurement tools designed to fully
exercise the host interface and tape drive with the least amount of
overhead. As such, the primary goal of the benchmarks was to provide a
picture of the maximum capabilities of the LTO-6 tape drive. All data
rates/capacity reflect a decimal basis where MB = 1,000,000 bytes and
GB=1,000 MB. Actual tape drive data rate and cartridge capacity might
vary depending on factors such as data compression, server and disk
performance variables.
There are a number of factors that impact performance, especially data
rate at high compression ratios and large block sizes. Server hardware
performance, server slot and operating system/device driver
performance are important factors. Another source of variability in the
data rate performance tests could be due to the firmware used for the
Fibre Channel and SAS connections.
Since this white paper is primarily concerned with looking at LTO-6 tape
drive capabilities, it is beyond the scope of this whitepaper to attempt to
present a complete picture of the relative performance characteristics of
all possible host server/HBA/tape drive combinations. However, when
appropriate an attempt will be made to provide some idea of how
operating system or HBA selection can affect data rate performance.
Page 3
5. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
Fibre Channel Data Rate Performance
The data rate performance of the IBM LTO-6 Fibre Channel full height tape drive
is described by the following set of charts that show how the drive behaves when
writing or reading data that compresses uniformly at ratios 1:1, 2:1, 2.5:1, 3:1 and
maximum (80:1) using differing block sizes and LTO gen6 media.
The IBM LTO-6 tape drive
achieves a native data rate of
160 MB/s with LTO gen6 media.
Higher rates are reached with
compressible data and the new
2.5:1 compression engine.
LTO6 FC FH Write Data Rates Gen6 Media
0
100
200
300
400
500
600
700
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
LTO6 FC FH Read Data Rates Gen6 Media
0
100
200
300
400
500
600
700
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
Page 4
6. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
The following charts show the IBM LTO-6 Fibre Channel full height tape drive
performance when writing or reading LTO gen5 media with data that compresses
uniformly at ratios 1:1, 2:1, 2.5:1, 3:1 and maximum (80:1) using differing block
sizes.
The LTO-6 drive can read and
write LTO gen5 media at the LTO
generation 5 operating point.
With no compressible data a
data rate of 140 MB/s is
achieved.
LTO6 FC FH Write Data Rates Gen5 Media
0
100
200
300
400
500
600
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
LTO6 FC FH Read Data Rates Gen5 Media
0
100
200
300
400
500
600
700
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
Page 5
7. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
The following set of charts show streaming data rate performance of the IBM
LTO-6 Fiber Channel half height tape drive when writing or reading data that
compresses uniformly at ratios 1:1, 2:1, 2.5:1, 3:1 and maximum (80:1) using
differing block sizes and LTO gen6 media.
The half height form factor drive
provides similar streaming
performance as compared with
the full height drive.
LTO6 FC HH Write Data Rates Gen6 Media
0
100
200
300
400
500
600
700
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
LTO6 FC HH Read Data Rates Gen6 Media
0
100
200
300
400
500
600
700
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
Page 6
8. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
The following set of charts describe the IBM LTO-6 Fibre Channel half height tape
drive performance when writing or reading LTO gen5 media with data that
compresses uniformly at ratios 1:1, 2:1, 2.5:1, 3:1 and maximum (80:1) using
differing block sizes.
The half height form factor drive
can read and write LTO Gen5
media with similar rates as
compared with the full height
drive with LTO Gen5 media.
LTO6 FC HH Write Data Rates Gen5 Media
0
100
200
300
400
500
600
700
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
LTO6 FC HH Read Data Rates Gen5 Media
0
100
200
300
400
500
600
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
Page 7
9. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
The above performance benchmarks show IBM LTO-6 Fibre Channel
tape drive performance (full height and half height models) from one or
more of the systems: IBM system x3850 running RHEL 6.1 with a
QLogic® QLE2562 HBA, IBM system x3755 running SUSE 11 SP1 with
a QLogic® QLE2562 HBA and IBM system x3250 running SUSE 11 SP2
with a QLogic® QLE2562 HBA. It must be noted that results from the
IBM system x3850 for Max compression ratio at 512KB block size
dropped about 9% from those shown, however, the rest of the data rates
for all the compression ratios and block sizes were consistent on all
systems. In this case, some aspect of the host-side configuration
decreased the system data rate performance for the specific case
mentioned.
Page 8
10. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
SAS Data Rate Performance
The data rate performance of the IBM LTO-6 SAS full height tape drive is
described by the following set of charts that show how the drive behaves when
writing or reading data that compresses uniformly at ratios 1:1, 2:1, 2.5:1, 3:1 and
maximum (80:1) using differing block sizes and LTO gen6 media.
The SAS data rate performance
capability of the IBM LTO-6 full
height drive meets expectations
at all compression ratios.
LTO6 SAS FH Write Data Rate Gen6 Media
0
50
100
150
200
250
300
350
400
450
500
550
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
LTO6 SAS FH Read Data Rate Gen6 Media
0
50
100
150
200
250
300
350
400
450
500
550
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
Page 9
11. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
The following charts show the IBM LTO-6 SAS full height tape drive performance
when writing or reading LTO gen5 media with data that compresses uniformly at
ratios 1:1, 2:1, 2.5:1, 3:1 and maximum (80:1) using differing block sizes.
The LTO-6 SAS full height drive
meets the LTO gen5 data rates
expectations when using LTO
gen5 media.
LTO6 SAS FH Write Data Rates Gen5 Media
0
50
100
150
200
250
300
350
400
450
500
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
LTO6 SAS FH Read Data Rates Gen5 Media
0
50
100
150
200
250
300
350
400
450
500
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
Page 10
12. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
The following set of charts show streaming data rate performance of the IBM
LTO-6 SAS half height tape drive when writing or reading data that compresses
uniformly at ratios 1:1, 2:1, 2.5:1, 3:1 and maximum (80:1) using differing block
sizes and LTO gen6 media.
The LTO-6 SAS half height form
factor drive provides similar
streaming performance as
compared with the SAS full
height drive.
LTO6 SAS HH Write Data Rates Gen6 Media
0
50
100
150
200
250
300
350
400
450
500
550
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
LTO6 SAS HH Read Data Rates Gen6 Media
0
50
100
150
200
250
300
350
400
450
500
550
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
Page 11
13. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
The following charts show the LTO-6 SAS half height tape drive performance
when writing or reading LTO gen5 media with data that compresses uniformly at
ratios 1:1, 2:1, 2.5:1, 3:1 and maximum (80:1) using differing block sizes.
LTO6 SAS HH Write Data Rates Gen5 Media
0
50
100
150
200
250
300
350
400
450
500
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
LTO6 SAS HH Read Data Rates Gen5 Media
0
50
100
150
200
250
300
350
400
450
500
32 64 128 256 512
Block Size (KB)
Data
Rate
(MB/s)
1:1
2:1
2.5:1
3:1
Max
Page 12
14. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
Tape Capacity
The following chart shows the capacity for LTO gen6 and LTO gen5 media
measured with the LTO-6 tape drive. Tape capacity is obtained by writing 256KB
blocks of uncompressible data until an error code is returned when EOT (End Of
Tape) is reached. The LTO-6 tape drive with gen6 media increases about 67%
over gen5 tape cartridge capacity offering a native physical capacity of 2500GB
while maintaining the 1500 GB expectation with gen5 media.
The LTO-6 tape drive with gen6
media offers a significant
capacity increase over gen5
media.
Tape Capacity
0
500
1000
1500
2000
2500
FC FH FC HH SAS FH SAS HH
Capacity
(GB)
Gen6 Media
Gen5 Media
Page 13
15. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
Locate and Rewind Performance
The following charts show the average time for the LTO-6 drive to locate a
random block id on the tape starting at BOT (Beginning Of Tape), the average
time to locate a random block id starting at some random location on the tape, the
average rewind time as well as maximum times measured for the three
operations. To determine average and maximum times, plenty locate and rewind
operations were made on a completely filled tape.
The full height form factor drives offer faster locate and rewind
performance than the half height form factor drives when using LTO gen6
media. With LTO gen5 media, a similar difference is observed.
The full height form factor drives
offer faster locate and rewind
performance than the half height
form factor drives when using
LTO gen6 media.
LTO6 SAS and FC Locate and Rewind Times
Gen6 Media
91.91
112.1
120.15
49.58
34.28
48.97
103.6
107.9
109.2
56.6
40.7
55.7
92
88.4
97.89
48.8
33.2
48.3
106
120.98
55.6
39.9
55.7
106.81
0
15
30
45
60
75
90
105
120
Avg BOT
Locate
Avg RND
Locate
Avg Rewind Max BOT
Locate
Max RND
Locate
Max Rewind
Seconds
FH FC
HH FC
FH SAS
HH SAS
LTO6 SAS and FC Locate and Rewind Times
Gen5 Media
92.93
92.65
98.53
47.72
38.12
51.01
100.01
100.73
101.66
54.1
38.08
51.94
92.87
93.06
98.12
48
38.26
50.95
99.74
108.06
107.37
53.58
45.41
57.01
0
20
40
60
80
100
120
Avg BOT
Locate
Avg RND
Locate
Avg Rewind Max BOT
Locate
Max RND
Locate
Max Rewind
Seconds
FHFC
HHFC
FHSAS
HHSAS
Page 14
16. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
Load and Unload Performance
The following charts show the tape cartridge load and unload times for the LTO-6
tape drive with LTO gen6 and LTO gen5 media. The performance when loading a
cartridge is slightly better for the full height drives. The time to unload a cartridge
is faster for the full height drives and there is no significant difference regarding
the interface type used.
The IBM LTO-6 tape drive has good
load performance for all form
factors, generation media and
interface types. The time to unload a
cartridge is faster for the full height
form factor drives for both gen6 and
gen5 media.
LTO6 SAS and FC Load and Unload Times
Gen5 Media
11.4
22.26
9.8
17.28
11.48
22.62
9.85
17.35
0
5
10
15
20
25
Load Time Unload Time
Seconds
LTO6 HH FC
LTO6 FHFC
LTO6 HH SAS
LTO6 FHSAS
LTO6 SAS and FC Load and Unload Times
Gen6 Media
21.45
13.35
17.2
11.68
21.34
13.38
17.41
11.52
0
5
10
15
20
25
Load Time Unload Time
Seconds
LTO6 HH FC
LTO6 FH FC
LTO6 HH SAS
LTO6 FH SAS
Page 15
17. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
Speed Matching Performance
The IBM LTO-6 tape drive disposes of 14 defined speeds to match the host data
rate. The implementation of this feature allows to reduce the number of
backhitches when the net host data rate is less than the maximum drive native
data rate, reducing unnecessary tape motion, and may increase overall
performance in certain environments.
To perform this test, host delays are used to vary the speed of the data
from the host to the LTO-6 tape drive. At each host data rate the number
of datasets handled by each speed is recorded (A dataset is the unit of
writing for the drive on the physical tape side and consists of collection of
logical blocks, file marks, ECC, and other format attributes). The Y-axis
shows both the effective data rate and the number of datasets handled
by each speed for the host data rate (X-axis). The chart shows how the
drive selects the appropriate speed from the available 14 speeds to
match the host data rate and most of the datasets written are handled by
the suitable speed.
LTO6 FC FH Write Speed Matching
0
500
1000
1500
2000
2500
3000
3500
4000
32 48 65 82 95 111 124 137 149 159
Host Data Rate (MB/s)
Dataset
Count
0
20
40
60
80
100
120
140
160
180
s1
s2
s3
s4
s5
s6
s7
s8
s9
s10
s11
s12
s13
s14
DR
Speed matching helps to
improve the overall tape drive
data rate at lower host data
rates.
Page 16
18. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
Conclusions
Since the introduction of the first IBM LTO tape drive, every following generation
has incorporated new features and performance improvements to respond
storage needs, now the IBM LTO-6 tape drive in conjunction with the new LTO
gen6 media represents an efficient solution for todays growing storage
demands. Native capacity increase from 1500GB (gen5 media) to
2500GB (gen6 media) and even more with data that is compressible
(6250GB with 2.5:1 compression) while maintaining the same tape
length (846m). This capacity increase does not impact locate/rewind
performance and the faster mechanism for the half height form factors
improves performance for tape motion operations (locate/rewind times)
from previous half height drive generations.
In addition, the IBM LTO-6 tape drive continuous to support media
partitioning, encryption of data and WORM media.
All the improvements make the IBM LTO-6 tape drive suited for handling
backup, restore, and archive of higher data capacities at higher data
transfer rates as compared with the previous LTO-5 tape drive.
Page 17
20. IBM® System Storage® LTO Ultrium 6 Tape Drive
Tape Drive Performance White Paper
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PURPOSE OR NON-INFRINGEMENT. IBM shall have no responsibility
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The provision of the information contained herein is not intended to, and
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Inquiries regarding patent or copyright licenses should be made, in
writing, to:
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Page 19