HPE StoreEver performance
troubleshooting guide
Contents
Introduction .................................................................................................................................................................................................................................................................................... 2
Performance troubleshooting guidance .............................................................................................................................................................................................................. 2
Solving your performance issues ......................................................................................................................................................................................................................... 2
General recommendations ..........................................................................................................................................................................................................................................3
Disk and file system performance ....................................................................................................................................................................................................................... 5
Backup application configuration ........................................................................................................................................................................................................................ 8
Tape drive performance ............................................................................................................................................................................................................................................... 9
Conclusion .....................................................................................................................................................................................................................................................................................14
Useful links .................................................................................................................................................................................................................................................................................... 15
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Introduction
With Linear Tape-Open (LTO) Ultrium Generation 6 tape cartridges now enjoying a street price of less than one penny 1 (USD) per gigabyte and
the total worldwide tape storage media capacity shipped reaching record levels of over 6,338 PB in the fourth quarter of 2014 2 more data is being
stored on LTO tape than ever before. Even as the role of tape has shifted over the years, LTO tape has remained a critical component for the
modern data center.
As tape drives continue to witness massive improvements in terms of capacity and performance, achieving expected performance results in
complex environments can be challenging. The purpose of this document is to provide knowledge and tools to help identify where performancerelated problems are commonly found in backup and archiving environments while giving guidance on how to address any issues. This guide
assumes that backup and restore jobs are running correctly, just not as fast as expected. If backup or restore jobs are not working, please refer to
the backup and archiving vendor’s documentation.
This guide is ordered so that the most likely performance issues are discussed first. Hewlett Packard Enterprise recommends that this order is
followed when troubleshooting performance issues.
Performance troubleshooting guidance
Solving your performance issues
To analyze speed and performance, it is necessary to examine the entire backup and archive process as a system. The process of backing up and
restoring files involves many system components, from the files in the file system on the disk, through the backup server, and out to the library,
all managed by software running on an operating system. The backup process can only run as fast as the slowest component in the system.
How fast should it go?
To assess if there is a performance issue, you first need to have an understanding of how fast your tape drive can transfer data given the
compression rate of your data set. HPE StoreEver tape drives have varying levels of performance. To determine the maximum possible
throughput for a tape drive, multiply the native data rate of the tape drive, which can be found in the drive QuickSpecs, by the compression ratio
of the data being backed up. For example, 2:1 compressible data to an HPE Ultrium 15750 (LTO-7) with a native throughput of 300 MB/s can
achieve a data rate of up to 600 MB/s. Table 1 shows native performance information for various HPE StoreEver tape drives. HPE Ultrium drives
have the ability to match the speed of the tape drive to the data rate of the server. It is variable between the drive’s lowest and highest rates and
reduces tape repositions for any transfer rate within this range—thus reducing wear even if the server cannot keep up with the native
throughput of the drive. In cases where the maximum transfer speeds cannot be achieved, achieving the minimum transfer speeds for the tape
drive minimizes the drive having to stop/reposition/restart. The combination of data rate matching and large buffers in the LTO tape drives
minimizes the effects of failing to stream on the tape drive and media.
1
2
lto.org/2015/03/lto-program-announces-price-per-gigabyte-now-less-than-one-penny
h30507.www3.hp.com/t5/Around-the-Storage-Block-Blog/The-unstoppable-rise-of-tape-storage-continues/ba-p/180219#.VSKspvPnZaR
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Table 1. Tape drive throughput speed
TAPE DRIVE
MINIMUM NATIVE THROUGHPUT MB/s
MAXIMUM NATIVE THROUGHPUT MB/s
Ultrium 15750 (LTO-7 FH)
101
300
Ultrium 15000 (LTO-7 HH)
101
300
Ultrium 6650 (LTO-6 FH)
54
160
Ultrium 6250 (LTO-6 HH)
54
160
Ultrium 3280 (LTO-5 FH)
47
140
Ultrium 3000 (LTO-5 HH)
47
140
Ultrium 1760 (LTO-4 HH)
35
80
Compression ratios can vary a great deal. HPE tests show that not all data can be compressed equally. The compression ratio affects the amount
of data that can be stored on each tape cartridge, as well as the speed at which the tape drives can read or write that data. Data that is not
compressible will always limit the speed at which the drive can write or read data. Transfer rates for uncompressible data will never exceed the
maximum native throughput of the drive. Examples of files that compress well are plain text files and spreadsheets; files that compress poorly are
those that are either compressed as part of their format (such as, JPEG photographic files) or stored as compressed files (such as, .ZIP files
or .gz/.Z files on UNIX® platforms). Table 2 shows typical compression ratios of various applications.
Table 2. Typical file compression ratios
DATA TYPE
TYPICAL COMPRESSION
CAD
3.8:1
Spreadsheet/word processing
2.5:1
Typical file/print server
2.0:1
Lotus Notes databases
1.6:1
Microsoft® Exchange/SQL Server databases
1.4:1
Oracle/SAP® databases
1.2:1
General recommendations
There are several general recommendations to consider regarding backup and restore performance with libraries and/or tape drives:
Table 3. Recommendations when connecting a tape library directly to a server
HPE LTO TAPE DRIVE MODEL
NUMBER OF DRIVES CONNECTED TO
A 4 GB/s FIBRE CHANNEL HBA*
NUMBER OF DRIVES CONNECTED TO
A 8 GB/s FIBRE CHANNEL HBA*
NUMBER OF DRIVES CONNECTED TO
A 16 GB/s FIBRE CHANNEL HBA*
LTO-4 Ultrium
2
4
8
LTO-5 Ultrium
1
2
5
LTO-6 Ultrium
1
2
4
LTO-7 Ultrium
1
1
2
*Assumes no other devices are attached to the FC HBA
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•
In a SAN environment, all FC switches between the host and the library must be of the appropriate type. The maximum rate for an FC
connection is the speed of the slowest component. An FC switch that is slower than the HBA or is heavily loaded will limit the performance.
•
A server that uses FC disks should have at least two FC ports. Using the same port for disk and tape access can cause performance
degradation. If you are going to read from storage connected to the same FC link that you are using for writing to tape, then that link must be
more than 2X the speed of the tape drive if you want to achieve maximum transfer speeds. If the storage device that is being read from has a
maximum transfer rate, which is able to consume most of the FC link capacity, and the backup application is caching data before sending it to
tape, then extended times reading can cause the drive to drop out of streaming. If a link is shared between tape and disk, Hewlett Packard
Enterprise recommends:
– Absolute minimum FC link rate = 2.2 x the minimum streaming rate of the tape drive being used
– Recommended minimum FC link rate = 1.2 x the maximum sequential read rate of read device x the minimum streaming rate of the tape
drive being used
– Optimal FC link rate = 1.2 x the maximum sequential read rate of read device x (2.5 x the native transfer rate of the tape drive being used)
•
Configure zoning on the FC switch so only the backup servers may access the library. See the switch manual for information on zoning.
•
Check the HPE Data Agile BURA Compatibility Matrix to verify that your FC or SAS HBA is supported with your server, running the
recommended firmware version, and qualified for the library and/or tape drives. You should also verify that the server and operating system
you are using are supported with the specific library and/or tape drives.
•
Most SAS HBAs have four SAS channels and can support up to four tape drives without seeing performance issues provided that the SAS HBA
is connected to the correct type of slot (e.g., PCIe-3).
•
If any backups require moving data across the Ethernet network (often done for remote office servers), this may introduce a bottleneck, which
impacts performance even with a gigabit connection. When performance is a concern for backups over the network (Ethernet), the network
bandwidth should be checked first.
•
For optimum performance, Hewlett Packard Enterprise recommends using HPE-branded cartridges that match the specification of your tape
drive:
– HPE LTO-7 Ultrium 15TB RW and LTO-7 Ultrium 15TB WORM cartridges for use with LTO-7 tape drives
– HPE LTO-6 Ultrium 6.25TB RW and LTO-6 Ultrium 6.25TB WORM cartridges for use with LTO-6 tape drives
– HPE LTO-5 Ultrium 3TB RW and LTO-5 Ultrium 3TB WORM tape cartridges for use with LTO-5 tape drives
– HPE LTO-4 Ultrium 1.6TB RW and Ultrium 1.6TB WORM tape cartridges for use with LTO-4 tape drives
•
LTO tape drives are able to read/write one generation back and read backwards two generations, but the performance when accessing earlier
generations is reduced from the specified native rates. See table 4 for more details.
Table 4. Data cartridge compatibility
HPE LTO TAPE
DRIVE MODEL
ULTRIUM
200GB* DATA
CARTRIDGE
ULTRIUM
400GB* DATA
CARTRIDGE
ULTRIUM
800GB* DATA
CARTRIDGE
ULTRIUM 1.6TB*
DATA
CARTRIDGE
ULTRIUM 3TB*
DATA
CARTRIDGE
ULTRIUM
6.25TB** DATA
CARTRIDGE
ULTRIUM 15TB**
DATA
CARTRIDGE
LTO-7 Ultrium
15750
Not supported
Not supported
Not supported
Not supported
Read only
Read/write
and WORM
Read/write
and WORM
LTO-6 Ultrium
6650
Not supported
Not supported
Not supported
Read only
Read/write and
WORM
Read/write
and WORM
Not supported
LTO-5 Ultrium
3280
Not supported
Not supported
Read only
Read/write and
WORM
Read/write and
WORM
Not supported
Not supported
LTO-4 Ultrium
1840
Not supported
Read only
Read/write and
WORM
Read/write and
WORM
Not supported
Not supported
Not supported
* Capacity assumes 2:1 compression
** Capacity assumes 2.5:1 compression
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•
LTO Ultrium tape drives use Ultrium tape cartridges. These are single-reel cartridges that match your drive’s format and are optimized for high
capacity, throughput, and reliability. Compatible media can be recognized by the Ultrium logo, which is the same as the logo on the front of
your drive. Do not use other format cartridges in your tape drive and do not use Ultrium cartridges in other format tape drives.
•
Hardware encryption can be used for the tape drives with or without compression and without speed or capacity penalties.
•
The backup server must have enough RAM and processor power to transfer the files from the disk to the tape drive, in addition to running the
backup or archive software and any other processes. Check the RAM and processor usage during a backup operation. It they are operating at
capacity, adding RAM or processor capability can improve performance.
Disk and file system performance
In the past, the tape drive was typically identified as the performance bottleneck. However, tape performance has now surpassed many of the
source systems available today. Items to consider when troubleshooting performance metrics include:
•
Source hardware (disk subsystems)
•
Source file system status
•
Server configuration
The following factors critically affect the speed of backup from disk to tape:
•
Data file size
The larger the number of smaller files, the larger the overhead associated with backing them up. The worst-case scenario for backup is large
numbers of small files due to system overhead of file accesses.
•
Data compressibility
Incompressible data will back up slower than highly compressible data. For example, JPEG files are not very compressible, but database files
can be highly compressible. The accepted standard for quoting tape backup specifications is a typical file system average figure of 2:1
compressible data for drives prior to LTO Generation 6, and 2.5:1 compressible data for LTO-6 and any future generations.
•
Disk array performance
It is often overlooked that data cannot be put onto tape any faster than it can be read from disk. Disk array performance depends on many
factors such as the number of disks, RAID configuration, the number of Fibre Channel ports accessing the array, and queue depth available, for
example.
•
Fragmentation
The more fragmented the files are on disk, the more random the disk access method will be. Hence, the backup will take longer. If the system
has a defragmentation utility, it is advisable to run it before full backups or on a regular scheduled basis to ensure that files are contiguously
arranged on the disk.
To measure the data transfer rate from the disk file system, run one of the system performance (Sys Perf) pre-tests of HPE Library and Tape
Tools (L&TT). Either the backup performance test, which measures the read performance of the disk file system, or the restore performance
test, which measures the write performance of the disk file system, can be run. See figure 1 as an example of the backup performance test. The
backup performance test parameters are:
•
The block size used to read data (1 KB up to 1024 K can be specified)
•
The type of directory traversal—the two options are:
– Read to the bottom of directory structure then traverse laterally, or
– Read breadth of each directory level before moving down in the structure
•
Set a time limit for the test to run or read all the data
•
Specify up to four directories to be read in parallel
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The reads are concurrent and can simulate up to four backup data streams. The performance of these reads is measured and reported in the
system performance results tab. See figure 2 as an example.
Figure 1. Configuring the backup performance test
Figure 2. Configuring the backup performance test
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Results in figure 2 are an example of performance testing only. Actual results will vary.
For the restore performance test, you can modify the following parameters:
•
The path where the data will be written
•
The compression ratio of the data
•
The range of file sizes
•
The directory structure
Refer to figure 3 as an example. Once the test completes, L&TT will ask if you want to delete the data set that was created during the test. The
results of the restore performance test can be viewed by selecting the system performance results tab.
Figure 3. Configuring the restore performance test
The disk file system performance tests measure the server’s ability to send data to a device or receive data from a device:
•
Data is read by the server in order to send it to a null device
– Block size, directory structure, number of threads, and data compressibility are all factors
•
Data generated in system memory is written to disk by the server
– Directory structure, file size, and compressibility are all factors
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Use the backup performance and restore performance tests to identify if there are performance bottlenecks in the disk file system. The backup
performance test is read-only and can be safely run on the backup source data. Using L&TT to get the actual read and write transfer rates that
the disk file system can provide lets you compare those results with the expected data transfer rate for the tape drive. If the disk file system does
not transfer data fast enough for the tape drive, then it will be a bottleneck.
Other considerations for improving disk and file system performance
• The connection between the backup server and the disks determines how much data can be transferred from the disks to the server at a time.
A connection with insufficient bandwidth cannot provide enough data for the tape drives to write at full speed. For optimum performance, the
storage subsystem must be able to provide data at the tape drive’s maximum transfer rate. The aggregation of multiple client sources over a
network provides a good way of delivering good performance, but anything less than Gigabit Ethernet will limit performance when using more
than a single LTO Ultrium tape drive.
•
When possible, avoid other applications accessing the disk file system such as virus scans. Optimally schedule access by other applications at
times when backups and restores are not running. Also, ensure that your antivirus software has been configured to exclude the files and
folders being backed up from the on-access virus scans to avoid a significant impact on performance.
Backup application configuration
If neither the disk nor file system are determined to be the performance limiters in the system, the next, most likely contender is the backup
application.
Each backup method has its own impact on performance, depending on how well it can keep data streaming to the tape drive. In most cases,
native applications don’t have the features required to maximize performance for LTO Ultrium tape drives. Hewlett Packard Enterprise
recommends using a full-featured backup or archive application as some enterprise-class backup and archiving applications can be made to
interleave data from multiple sources, such as clients or disks, to keep the tape drive working at optimum performance.
Block size
When a device receives data, it processes it in blocks of data. Different devices have different optimal block sizes that can be used. By adjusting
the block size, you can enhance the performance of the backup application.
Each backup application will support a specific—and likely different—range of block sizes. Check for supported block sizes of the current host
adapter before using a higher block size. For the best HBA compatibility and performance, Hewlett Packard Enterprise recommends using a
block size of 256 KB for LTO-4 and newer tape drives. Small performance gains can be seen using higher block sizes but not all HBAs support
block sizes larger than 256 KB.
Warning
Several backup applications can only append to media with the same block size as was originally written to that media. You should change the
block size before formatting tapes. Most applications write the block size into the media header so that the backup application knows the size to
be used. If the device block size differs from the media block size, an error occurs.
Before increasing the block size for a device, make sure the desired block size does not exceed the default maximum block size supported by the
operating system using the device. If the limitation is exceeded, the backup application cannot restore data using that device. For information on
if and how the maximum supported block size can be adjusted, see the operating system documentation.
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File-by-file vs. image or sequential backups
One of the biggest performance gains can be made by switching from file-by-file backups to image or sequential backups. File-by-file backup or
archive methods provide the best restore performance if you only need to restore individual files. However, if the average file size is small, file-byfile methods will significantly reduce performance. Disk image, flash, or sequential backup methods provide the fastest performance because they
back up an entire disk, partition, or LUN, which minimizes disk seeking. There are significant disadvantages to performing backups in image
mode so carefully consider them before making the switch.
•
Image mode is a complete backup of a single partition or LUN. A subset, such as a file or set of files, cannot be backed up in this way.
•
When restoring, the complete partition (or LUN) must be restored as a single operation unless the application is able to extract the required
data itself. This can add considerable time to a selective restore.
•
Unless doing a full restore, a spare partition may be needed to restore to, so as not to overwrite data in the active partition.
The trade-off is effectively between backup performance and ease of restoring subsets of the partition or LUN.
Database backup performance will vary based on the use model. To improve performance when backing up data from a database:
•
Use specific backup agents for the database.
•
Use the latest versions of the databases.
•
For Microsoft Exchange, backup database files rather than individual mailboxes.
•
When backing up specific records, such as Oracle for example, backup datafiles rather than tablespaces.
•
Backup the database during off hours when it is in lighter use.
Additional recommendations for achieving high performance with backup and archive applications
• Make sure that any software compression being used by the backup or archive application is turned off. Not only is the hardware compression
of the tape drives faster, but compressing data twice tends to give non-optimal compression ratios with DDS drives (LTO drives detect
compressed data and do not attempt further compression.).
•
If possible, increase the system memory allocated to the backup application.
•
Use multi-threading (concurrency) if possible, which allows multiple backups to be interleaved to the tape, thus reducing the effect of disk
seeks for each backup. This can have an impact on restore times as a particular file set is interleaved amongst other data.
Tape drive performance
If the backup or restore job performance is still not as expected, continue the performance troubleshooting process by assessing the tape drive.
This can be done by verifying how fast the server can access the tape drive independent of the disk subsystem and backup solution. HPE Library
and Tape Tools (L&TT) can be used to transfer preloaded data using different compression ratios directly from the memory of the server to the
tape drive. L&TT is a free, downloadable, robust diagnostic tool for all of HPE StoreEver tape storage. L&TT is ideal for verifying that all tape
devices are installed and detected by the backup server as well as to perform diagnostics and achieve faster resolution of tape device issues.
Before you run L&TT performance tests to check the tape drive performance, verify the following:
•
Fibre Channel (FC) or Serial Attached SCSI (SAS) Cabling
– The cable(s) might not be plugged in completely or correctly. Verify that all cables are securely connected on both ends.
– Check the integrity of the cables as one or more cables could be damaged. FC cables in particular are delicate. If the cable has been bent or
twisted sharply, it might be broken and will need to be replaced.
– Check the connectors at both ends of the cable(s) and on the drives for damage or debris.
– SAS cables should not be longer than six meters and do not use a cable adapter or converters between the HBA and the tape library.
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Login to the tape library using the Web-based interface (http://<library hostname or IP address>) and verify that the link connection for the
tape drive(s) is good
– From the main screen, for an MSL G3 (2024/4048/8048/8096), click the Status tab among the five tabs at the top of the screen. Next,
select the Drive tab directly below the Status tab.
– From the home screen, for an MSL6480, click the Status tab, then select Drive Status on the right portion of the next page that is
displayed.
– From the home screen, for an ESL G3, click Monitor, then select Drives from the drop-down menu.
•
If any drives are listed with connection issues
– Confirm that the FC speed listed for each tape drive is the expected speed. If you are uncertain of the speed of the HBA or FC switch, verify
that the FC connection speed for each tape drive is set to Automatic.
– If changing the FC speed for the tape drive doesn’t resolve the connection issues, change the port type to Automatic (MSL G3 or MSL6480)
or the topology to Fabric (ESL G3).
– If an ALPA conflict is displayed, there might be a conflict with the ALPA address on loop ports. Select Soft for the Addressing Mode (MSL
G3 or MSL6480), or Loop ID (ESL G3), to allow the system to select an available address each time the tape drive connects to the FC fabric.
The addressing mode or topology must be modified to loop for all libraries before Soft can be selected. If your server configuration does not
support changing addresses, try using the Hard Auto-Select option for the Loop mode. This allows the system to select an available
address when it first connects, and retains that address for future connections.
– The tape drive settings listed can be changed by accessing the configuration page for the tape drives:
 For an MSL G3, click the Configuration tab among the five tabs at the top of the Web-based interface. Next, select the Drive tab directly
below the Configuration tab.
 For an MSL6480, select the Configuration tab on the main screen, then click Drives from the list on the right side of the page. This will
take you to the Settings page. Click the triangle to the left of the drive to expand that drive. You will see configuration settings for both
FC ports on the drive.
 For an ESL G3, click Setup, then choose Drive Settings.
•
Verify that no additional devices are connected to the same FC or SAS HBA/SCSI bus that the tape library and/or tape drives are connected to.
High-speed tape drives must have exclusive access to the HBA/SCSI bus to achieve their potential data transfer rates.
•
Verify that the data being sent from all HBAs to the tape library and/or drives is balanced. Take, for example, a SAN with 8 GB/s Fibre Channel
HBAs and switch, LTO-6 drives, and mixed data sets that are highly compressible (2:1 compression or greater) can transfer data up to 320
MB/s to 400 MB/s per drive. This amounts to an ideal configuration of one HBA port per two to three drives, and avoids a data bottleneck.
A well-tuned configuration has the bandwidth of each HBA port-to-switch connection greater than the sum of the traffic for each drive it is
transferring data to or from. Figure 4 is a simple LTO-6 example using a single server with an 8 GB/s switch and a non-compressible data set,
which shows the HBA can keep four drives streaming whereas if the data being backed up was instead a highly compressible data set, then
the number of drives required would be reduced to three or two.
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Figure 4. Balancing the data traffic
•
When a tape becomes damaged or heavily worn, the drive will perform retries to successfully write/read the data. If a large number of retries
are required, this will result in a drop in performance of the drive. To resolve these issues, either perform a media assessment test using L&TT,
try using a new tape, or use a tape that has only been written to a few times.
•
Use a cleaning cartridge whenever the drive has illuminated the cleaning indicator. As the drive is used, media debris can accumulate at the
head-tape interface; use of the cleaning cartridge can help reduce the impact of this debris.
•
You can use HPE StoreEver TapeAssure Advanced, which is a licensed feature of HPE Command View for Tape Libraries software, to view a
dashboard display with pie charts, live and historical graphs for performance, health, and utilization data for your drives and tapes, and
highlights issues in your tape infrastructure. Advanced analytics feature makes use of predictive analytics to predict the likelihood of failures,
bottlenecks, and load-balancing issues in the tape infrastructure. The technical white paper, Managing and optimizing HP (now HPE)
StoreEver Tape Libraries, contains detailed instructions for using Command View for Tape Libraries including the TapeAssure Advanced
feature.
•
Use the HPE Data Agile Backup, Recovery, and Archive (BURA) Compatibility Matrix to verify that the HBA, HBA firmware, operating system,
and drivers installed are supported and up-to-date.
Once you have verified that none of the factors listed are causing the performance issues, then you can use L&TT to verify the performance of
the tape drive.
Caution
Running L&TT while other software is accessing the storage devices can cause unpredictable results and adversely affect the operation of the
L&TT software. Any backup applications and the associated services must be stopped before using L&TT.
Start by using L&TT to view details for the library and/or drives by clicking the By Product tab. See figure 5 as an example. You can confirm the
firmware versions that are installed as well as check if there are any customer advisories for your devices.
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Figure 5. Selecting the device in L&TT
To test the tape drive performance by writing and reading data to or from the chosen tape drive, select the drive performance (Dev Perf) test of
L&TT. See figure 6 as an example.
Figure 6. L&TT device performance test
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Each of the selected drives will be tested in parallel. Hewlett Packard Enterprise recommends selecting a single drive for testing to start. You can
click the Options button to configure the test data. See figure 7 as an example. Options for the drive performance test include:
•
Type of compression—simulating different data types
•
Block mode—fixed or variable
•
Block size—when the block mode is set to fixed, the size of the data blocks used in the test can be specified
•
I/O size—maximum data transferred during a single read/write operation
•
Test size—maximum amount of data written/read by the test
•
File mark mode—instructs the test when to write a file mark at the specified interval
•
Read after write—when enabled, data is written to the tape and then the tape is read back. When disabled, only write performance is measured
•
Rate limiting—I/O rate is limited to the specified value
•
Compare after read—checks the integrity of the data but reduces the transfer rate of the test. Performance is not reported when this option is
selected
Warning
The drive performance test is destructive and will overwrite any data on the tape cartridge. To prevent any loss of data, use a blank tape or a
tape with expired or otherwise unneeded data when performing this test.
Figure 7. Options for the device performance test
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The performance of the read/write operations is measured and reported in the Drive Performance Results tab. See figure 8 as an example.
Figure 8. Drive performance test results
Device performance measures the ability of the tape drive to ingest/regurgitate data:
•
Data written to a tape drive is generated in memory—no file system overhead
•
Data read from a tape drive is discarded or stored in a flat directory structure to minimize overhead
For more detailed information regarding troubleshooting the tape drives, refer to the following documents:
HPE StoreEver MSL2024, MSL4048, MSL8048, and MSL8096 Tape Libraries User and Service Guide
HPE StoreEver MSL6480 Tape Library User and Service Guide
HPE StoreEver Enterprise System Library (ESL) G3 Tape Library User Guide
Conclusion
Even as the role of tape has shifted over the years, LTO tape has remained a critical component for the modern data center and more data is
being stored on LTO tape than ever before. As tape drives continue to witness massive improvements in terms of capacity and performance,
taking advantage of those performance improvements for tape drives in complex environments can be challenging. By leveraging this document,
storage administrators will develop the knowledge to identify where performance-related problems are commonly found in backup and archiving
environments.
Technical white paper
Useful links
HPE Data Agile Backup, Recovery, and Archive (BURA) solutions and compatibility matrices
HPE Library and Tape Tools
HPE StoreEver MSL Tape Libraries
HPE StoreEver MSL6480 Tape Library
HPE StoreEver ESL G3 Tape Libraries
Learn more at
hpe.com/storage/BURA
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