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Data Protector Tape Backup Performance
page 110 March 2009
DATA PROTECTOR
BACKUP PERFORMANCE
WITH
TAPE DRIVES
Data Protector Tape Backup Performance
page 210 March 2009
network-based backup
SAN backuplocal backup
Page 2
diskagent
via NDMP
media agentdisk
agent
application server
Cell manager
media agent(robotic control)
disk agent
media agent
storage area network
Cell manager
media agent
disk agent
Cell manager
tape
tapetape
tape
tape library
IDB IDB
IDB
30 MB/sec
30 MB/sec
LTO4Drives
20 ?????????MB/sec
30 + 30 = 20?60 MB/sec in. 20 MB/sec out.
2:1 Compression
GbitLAN
Data Protector Tape Backup Performance
page 310 March 2009
In This Presentation Performance - What do we mean? Is there a performance issue? Is there a performance issue for HP DP Support? Proviso Why HP DP Support does not “do” performance. Why HP DP Support does help with performance. Streaming – The Secret to High Performance Stream-Fail – The Secret to Dismal Performance Data collection Analysis Options Reference
Data Protector Tape Backup Performance
page 410 March 2009
What does performance mean?
In this presentation we are talking about how fast a Backup backs up data to tape.
This is not about Restores, although similar. This is not about Virtual Tape. This is about Physical Tape.
o All drive references here are to LTO/Ultrium, but, except that Ultrium drives have a range of streaming rates, while other drives have a single rate, the same principles apply to all commonly used backup tape drives.
Data Protector Tape Backup Performance
page 510 March 2009
Performance
“Performance” can mean a number. “Performance” can mean efficiency. “Performance” can be subjective.
o A customer who upgrades from DLT8000 to LTO3 might be pleased with the faster backups, and not realize the performance is poor compared to the capability of the LTO3.
o Or that customer might be very displeased because the LTO3 backup could be slower than the DLT8000 backup. We’ll see why.
Data Protector Tape Backup Performance
page 610 March 2009
Is There a Performance Issue?
Calculate:
Bytes backed up
Divided by time
Divided by number of drives
Equals performance:how many bytes per second/minute/hour per drive.
Is this value within the STREAMING range for the drive? No – a performance issue. An issue for HP DP Support? Sometimes.
Data Protector Tape Backup Performance
page 710 March 2009
An issue for HP DP Support?Things To Check
Recent changes? Patches? Upgrade? New drive? Patch – does backing out the patch help? Upgrade – to 6.00? 6.10?
o writedb/readdb to defragment the Filenames tablespace, then keep an eye on it (omnidbutil –info).
New drive? Customer claims “no compression”? o Probably not a Data Protector issue. More likely the backup is not
streaming, which takes longer and reduces tape capacity.
Data Protector Tape Backup Performance
page 810 March 2009
Borderline cases
Added an object to the backup and now it takes twice as long. Two backups of same size, one takes much longer. “Same” backup in another Cell is twice as fast.
In cases like these, HP DP Support probably will explain streaming, give advice, URLs, proviso (slide 10).
Data Protector Tape Backup Performance
page 910 March 2009
Proviso (1)
AFTER conversation with customer, understanding the issue and agreeing to provide some guidance for a performance issue, HP DP Support will send advice along with a proviso.
Data Protector Tape Backup Performance
page 10
10 March 2009
Proviso (2)For Customers
_________________________________________________________________________
Please note that, in the absence of errors, performance analysis and tuning
is not a Response Center service for Data Protector. However, I am familiar
with some of the issues and may be able to offer some advice. If my advice
does not help, you may wish to obtain the services of a performance
specialist.
There is excellent performance guidance at this website:
HP Surestore and StorageWorks - Performance Troubleshooting and Using
Performance Assessment Tools
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=lpg50460
This whitepaper for the Ultrium 960 discusses performance issues.
http://h71028.www7.hp.com/ERC/downloads/5982-9971EN.pdf
If email puts a space in the URL, just remove it. There are no spaces in these URLs._________________________________________________________________________
Data Protector Tape Backup Performance
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10 March 2009
Why HP DP Support Does Not “do” performance
HP DP Support supports the Data Protector product, not its entire environment.
HP DP Support does not control the environment that Data Protector operates in.
HP DP Support personnel are not and cannot be sufficiently familiar with customer’s Data Protector environment.
There are many factors outside Data Protector that affect performance.
Performance analysis and tuning is its own specialty.
Data Protector Tape Backup Performance
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10 March 2009
Why HP DP Support DOES help with performance
HP DP Support personnel:• Know some of the factors that customer might not know.• Know some of the common problems and solutions.• Know of Data Protector issues.• Know the options in Data Protector.
Data Protector Tape Backup Performance
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10 March 2009
S T R E A M I N G
The
obscure, misunderstood, esoteric, recondite, abstruse, arcane, shadowy,
unseen, unnoticed
component
in tape backup performance.
Data Protector Tape Backup Performance
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10 March 2009
Streaming – The Secret to High Performance
Streaming: moving the tape continuously during a backup - Never stop/start.
Streaming requires that data be delivered to the drive above the minimum streaming rate.
Tape drives perform best when they are streaming. Tapes hold the most data when streaming – 100% of
capacity. Performance degrades severely and precipitously when
streaming is not achieved (“stream-fail”). Stream-fail dramatically reduces capacity.
Data Protector Tape Backup Performance
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10 March 2009
Streaming Rate Varies with Compression(1)
No compression, the drive writes one byte of data for each one byte received. One byte in – one byte out.
2:1 compression, the drive writes one byte for each two bytes received. Two bytes in – one byte out.
4:1 compression, the drive writes one byte for each four bytes received. Four bytes in – one byte out.
8:1 compression, the drive writes one byte for each eight bytes received. Eight bytes in – one byte out.
The greater the compression, the faster the data must be delivered to write that one byte.
Data Protector Tape Backup Performance
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10 March 2009
Streaming Rate Varies with Compression (2)
LTO1 minimum streaming rate with no compression is 6 MB/second.
LTO1 minimum streaming rate with 2:1 compression is 12 MB/second.
LTO1 minimum streaming rate with 4:1 compression is 24 MB/second.
LTO1 minimum streaming rate with 8:1 compression is 48 MB/second.
LTO4 minimum streaming rate with 8:1 compression is 320 MB/second!
Data must be delivered at these rates so the drive can stream the data onto the tape.
Lower data delivery rate results in stream-fail.
Data Protector Tape Backup Performance
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10 March 2009
S T R E A M I N G
Big deal!
Of course modern tape drives are fast.
So what?
Data Protector Tape Backup Performance
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10 March 2009
People naturally expect that when the rate of data delivery slows down the backup will slow down at about the same rate.
Data Protector Tape Backup Performance
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10 March 2009
It’s much worse than that!
Performance drops precipitously, down to less than 1% of best performance, because of repeated repositioning (0.25 – 3 seconds each time).
Data Protector Tape Backup Performance
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10 March 2009
Stream-Fail – The Secret to DISMAL Performance Stream-fail
o Costs Timeo Costs Capacity
When the rate of data delivery drops below the streaming rate, the tape repositions – stop, reverse, forward, stop – known as the “shoe-shining” effect. This is “stream-fail”.
Each stream-fail costs 0.25 - 3 seconds. Each stream-fail leaves 10-100 MB of position-markers on
the tape between data blocks. Stream-fail can reduce performance to less than 1% and
capacity to 8% or less! We Want STREAMING.
We Don’t Want “S T R E A M – F A I L” bad bad bad bad bad bad bad bad bad bad bad bad bad bad bad bad
Data Protector Tape Backup Performance
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10 March 2009
True Story (1)
RCE said customer’s new LTO3 was not compressing. How did he know? How did he conclude this?
The tape was full at 50 GB and it took 8 hours to get full!
Hmmmm. LTO3 at 2:1 compression can put 800 GB on a tape and will put 50 GB on that tape in 6-18 minutes, but needs to receive 54-240 MB/second to do it.
NOTE that the compression factor is stated. It is needed to calculate the streaming rate for compressed data.
He was backing up one filesystem from a simple disk.
Reading the filesystem at perhaps 6 MB/s – far short of 54 MB/s.
NOT STREAMING! NOT EVEN CLOSE!
He had 50 GB of data intermixed with 750 GB of non-data gaps from stream-fails!
Data Protector Tape Backup Performance
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10 March 2009
True Story (2)
Stream-Fail Reduces Capacity
Streamed tape-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
datadatadatadatadatadatadatadatadatadatadatadatadatadatadatadatadata-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
data = 100% of tape Elapsed time = 6-18 minutes
Stream-failed tape----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
data s p a c e data s p a c e data s p a c e data s p a c e data----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
data = 8% of tape non-data= 92% of tape
Elapsed time = 480 minutes = 8 hours 0.8% of best performance
Data Protector Tape Backup Performance
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10 March 2009
Did It Stream? 1 TB in ten hours @2:1 (1)
1 x LTO1 (40-100 GB/hour) - Streaming at top speed!
2 x LTO1 - ???
3 x LTO1 - Not
1 x LTO2 (67-200 GB/hour) - ???
2 x LTO2 - ???
3 x LTO2 - ???
1 x LTO3 (190-560 GB/hour) - ???
1 x LTO4 (290-860 GB/hour) - ???
Data Protector Tape Backup Performance
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10 March 2009
Did It Stream? 1 TB in ten hours @2:1 (2)
1 x LTO1 (40-100 GB/hour) - Streaming at top speed!
2 x LTO1 - Streaming at 50 GB/hour.
3 x LTO1 - Not! 33 GB/hour.
1 x LTO2 (67-200 GB/hour) - Streaming at 100 GB/hour.
2 x LTO2 - Not! 50 GB/hour.
3 x LTO2 - Not! 33 GB/hour.
1 x LTO3 (190-576 GB/hour) - No way! 100 GB/hour.
1 x LTO4 (288-864 GB/hour) - Sorry! 100 GB/hour.
Data Protector Tape Backup Performance
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10 March 2009
DATA
COLLECTION
Data Protector Tape Backup Performance
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10 March 2009
Data from Customer
How many tape drives? How many tapes? How much data was backed up? How long did it take? What kind of tape drive(s)? What generation cartridges? (LTO2 cartridge in LTO3 drive?)
Needed to calculate whether the backup streamed. Network backup or local backup? What is the network speed? How many Objects? (Filesystem on UNIX; Disk on Windows) Recent changes?
Data Protector Tape Backup Performance
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10 March 2009
NETWORK BACKUP OR LOCAL BACKUP?
Session Manager
SessionManager
Cell Manager
TCP/IP
TCP/IP
TCP/IP
Disk Agent
Media Agent
Disk Agent
Media Agent
TCP/IP
TCP/IP
Scheduler
Cell Console
Network Backup Local Backup
Shared Memory
Data Protector Tape Backup Performance
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10 March 2009
[Normal] From: BMA@server2.com "drive_5" Time: 05/21/05 03:01:23 STARTING Media Agent "drive_5"
[Normal] From: BMA@server2.com "drive_5" Time: 05/21/05 03:01:25 Loading medium from slot 50 to device /dev/rmt/2mn
[Normal] From: OB2BAR@server1.com “server1" Time: 05/21/05 03:02:39 Starting OB2BAR Backup: /dbs01/0 (dbspace)
[Normal] From: OB2BAR@server1.com “server1" Time: 05/21/05 03:18:47 Completed OB2BAR Backup: /dbs01/0 (dbspace)
[Normal] From: BMA@server2.com "drive_5" Time: 05/21/05 12:22:47 COMPLETED Media Agent "drive_5“
Backup Statistics: Session Queuing Time (hours) 0.00 ---------------------------------------- Completed Disk Agents ........ 62 Failed Disk Agents ........... 0 Aborted Disk Agents .......... 0 ----------------------------------------
Disk Agents Total ........... 62 ======================================== Completed Media Agents ....... 1 Failed Media Agents .......... 0 Aborted Media Agents ......... 0 ----------------------------------------
Media Agents Total .......... 1 ========================================
Mbytes Total .............270983 MB Used Media Total ............. 1 Disk Agent Errors Total ...... 0
Data in DP Session Session Report from GUI
or CLI
Command lineomnidb –session 2005/05/21-3 –report
Reports bytes per backup.
Use session_devices report to get bytes per drive.For capacity, you still must determine bytes per tape if multiple tapes.
Data Protector Tape Backup Performance
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10 March 2009
“Display Statistical Information”(1)Display
statistical info
Advanced options
Other tabOptions tab
Data Protector Tape Backup Performance
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10 March 2009
“Display Statistical Information” (2) Enable “Display Statistical Info” in the backup specification
(Backup GUI, select backup, Options tab, Filesystem Options, Advanced button, Other tab)
Statistical information is displayed for each Disk Agent in the Session Report.
[Normal] From: OB2BAR@server1.com “server1" Time: 05/21/05 03:02:39 Starting OB2BAR Backup: /dbs01/0 (dbspace)
Directories……… 0Regular Files….. 1-------------------------------------------------Objects Total….. 1
Kbytes Total….. 6181958 ---------- Note that this is KB, not MB.
At completion of Disk Agent:[Normal] From: OB2BAR@server1.com “server1" Time: 05/21/05 03:18:47 Backup Profile: Run Time ........... 0:16:08
Backup Speed ....... 6386.32 (KB/s) ---------- Note that this is KB, not MB.
Data Protector Tape Backup Performance
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10 March 2009
Session Objects Report To see each object’s performance
omnirpt -report session_objects -session <sess_ID>
omnirpt –report session_objects -session 2005/05/21-3
Session Objects ReportCell Manager: server1.comCreation Date: 05/23/05 11:29:03
Object Type Client Mountpoint Description Status Mode Start Time Duration [hh:mm] Size [kB] # Files Performance [MB/min] Protection # Errors # Warnings Device ________________________________________________________________________________BAR server1.com /dbs01/0 Informix Completed full 05/21/05 03:01:48 0:16
6181958 1 373.81 07/16/05 03:01:48 0 0 drive_5 BAR server1.com /dbs02/0 Informix Completed full 05/21/05 03:17:57 0:14
6187042 1 405.05 07/16/05 03:17:57 0 0 drive_5
Data Protector Tape Backup Performance
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10 March 2009
Session Devices Report To see a tape drive’s write rate
omnirpt -report session_devices -session <sess_ID>
omnirpt -report session_devices -session 2005/05/21-3
Session Devices ReportCell Manager: server1.comCreation Date: 05/23/05 11:28:18
Device Start End Duration GB Written Perf [GB/h] # Objects # Media_______________________________________________________________________________ drive_5 05/21/05 03:01:28 05/21/05 12:19:28 9:18 264.31 28.42 62 1
This is per drive, not per tape.
Data Protector Tape Backup Performance
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10 March 2009
Ob2TapeStatistics(1)
global file option Disabled by default
# Ob2TapeStatistics=0 or 1
# default: 0
# If enabled, this option allows tape statistics logging into
# media.log file.
Data Protector Tape Backup Performance
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10 March 2009
Ob2TapeStatistics(2)
Set in global file on Cell Managero Windows
C:\Program Files\OmniBack\Config\Server\Options\globalC:\ProgramData\OmniBack\Config\Server\Options\global
o UNIX/etc/opt/omni/server/options/global
Logged to media.log on Cell Managero Windows
C:\Program Files\OmniBack\log\Server\media.log C:\ProgramData\OmniBack\log\Server\media.log
o UNIX/var/opt/omni/server/log/media.log
Data Protector Tape Backup Performance
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Ob2TapeStatistics(3) Entries are placed in media.log upon close of media05/21/05 12:21:45 cf98e98f:403a4182:2e50:0001 "[DKL002] INFORMIX_60" [TAPE WRITE STATISTICS] logical drive=drive_5 errsubdel=59586 errposdel=0 total=744 toterrcorr=744 totcorralgproc=0 totb=97714108800 totuncorrerr=0
errsubdel = errors corrected with substantial delays errposdel = errors corrected with possible delays total = total number of re-writes toterrcorr = total errors corrected totcorralgproc = total number of times correction algorithm processed totb = total blocks processed, after compression.
This field has different units for different drive types. For many drives it’s bytes.o For LTO it’s the number of datasets, which is the Data Protector data within the data blocks.o For LTO1/2 the size of the dataset is 403,884 compressed bytes. Slightly larger for LTO3/4.o This value divided into the bytes sent to the drive (see Session report or Session Devices report) gives the
compression ratio.o totb x 403884 bytes = data-bytes-written-to-tapeo bytes-sent-to-drive-in-session / (data-bytes-written-to-tape 1 + data-bytes-written-to-tape 2 + ...) = compression ratio
NOTE: NEED TO SUM totb FOR ALL THE TAPES WRITTEN BY THE BACKUP BECAUSE
WE DO NOT HAVE SESSION-DATA-TO-DRIVE TOTALS FOR INDIVIDUAL TAPES.
totuncorrerr = total uncorrected errors Usually error counts will be very low. High error rates degrade performance and Merit a hardware call.
Data Protector Tape Backup Performance
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10 March 2009
A N A L Y S I S
Data Protector Tape Backup Performance
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10 March 2009
Measuring Backup Performance
What is the performance of each Disk Agent?o Are there enough DAs to achieve data delivery at the minimum
streaming rate? Compute overall compression ratio for the session.
o Find all the tapes in media.log and add up “totb” for them, divide into bytes backed up.
Calculate what would be a streaming number of tapes used. (For LTO3, one tape per 800 GB at 2:1)
Overall, how many bytes were sent to each drive?bytes-to-drives / session duration / # of drives = bytes per time per drive.o 1.6 TB per 2 hours per 2 drives = 800 GB per hour per 2 drives
= 400 GB per hour per driveo Is that a streaming rate for LTO3 with LTO3 cartridge at 2:1
compression? Is this within streaming range for the drive?
Data Protector Tape Backup Performance
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10 March 2009
Troubleshooting Media Agent Performance
Performance is: bytes written per time period per drive. Use “omnirpt -report session_devices -session <sess_ID>” plus
Ob2TapeStatistics to calculate compression rate. Must total the statistics for every tape written to all the drives that the
backup used. It is possible to calculate per drive only if you can determine which drive
used which tapes. UNFORTUNATELY, if a backup uses two or more drives, the only way to
determine which tapes were used in which drives is to use the Backup Session report and list the storage slots used by the BMAs, and to know which tapes were in those slots at the time of the backup. That slot-tape information is not available after a tape has been moved.
Test a drive’s performance independently of Data Protector with LTT - Library and Tape Tools
http://h18006.www1.hp.com/products/storageworks/ltt/index.html?jumpid=reg_R1002_USEN
Data Protector Tape Backup Performance
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10 March 2009
Troubleshooting Disk Agent (disk) performance
Use “session_objects” report Enable DP’s “Display Statistical Info”
o Shows object Backup Profile/Statistics in session report
Run VBDA (Volume Backup Disk Agent) standaloneo The standalone test shows what the Disk Agent actually can do
without being slowed down by tape drive repositioning. o Run test backup to /dev/null (Unix) or C:\nul (Windows).o “-profile” means “Display statistical info”.
/opt/omni/lbin/vbda –vol /opt –trees /opt/omni –out /dev/null –profile
Kbytes Total ………. 774347
Run Time ………….. 0:01:10
Backup Speed ……. 11062.10 (KB/s)
Data Protector Tape Backup Performance
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10 March 2009
network-based backup
local backup
Page 40
diskagent
via NDMP
media agent
disk agent
Cell manager
tapetape
IDB
SAN (LAN-free) backup
Troubleshooting
Network
Performance
Data Protector Tape Backup Performance
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10 March 2009
Troubleshooting Network performance
Network backup = DA and MA on different hosts. Network must have sufficient capacity to move data at high
rates.o 10BaseT (<1 MB/sec) and 100BaseT (<10 MB/sec) are slow
compared to current tape drive transfer rates.o 1000BaseT (<100 MB/sec) can handle some network backups.o 1000BaseT is insufficient for LTO3/LTO4 much above their minimum
streaming rates (54/80 MB/s) for no more than one of those drives.o Better performance is possible using SAN.
TEST: ftp large or many files between DA and MA hosts. TEST: Run test backup to a Data Protector drive defined
with /dev/null (Unix) or nul (Windows). TEST: Use PAT - Performance Analysis Tools
http://www.hp.com/support/pat
Data Protector Tape Backup Performance
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10 March 2009
- OPTIONS -
- SOLUTIONS -
- TUNING -
Data Protector Tape Backup Performance
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10 March 2009
Tuning for Performance (1)
Ensure current patches, firmware, drivers are installedo Data Protector, Operating System, Drives, Tape Library, NSR, SAN
Switch, etcetera.
Software Compressiono Don’t use it - causes high CPU overhead.
o If used, except for Ultrium/LTO, disable hardware compression,
otherwise non-LTO drive will produce larger blocks and run slower. Hardware Compression
o On by default.
Data Protector Tape Backup Performance
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10 March 2009
Tuning for Performance (2)Data Protector Settings
Block Sizeo Equivalent to data transfer size.o Should be at least 64KB.o Use the Data Protector default setting, except for LTO/Ultrium.o See “Whitepaper for the Ultrium 960” link in Reference section.
Segment Sizeo Defines the amount of data DP writes to tape before a catalog
segment is written.o Increasing this parameter will improve the importing speed of tapes
and may improve write performance.o Uses more memory on the MA host.
Data Protector Tape Backup Performance
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10 March 2009
Tuning for Performance (3)Data Protector Settings
Disk Agent bufferso Set in the Data Protector tape drive definition.o It’s the number of buffers set up in memory for Disk Agents on both
the Disk Agent host(s) and the BMA host.o The memory is shared if both the DAs and BMA are on the same host.o Default of 8 is reasonable.o Might help to increase number of buffers. Usually not helpful.
But in one case, Media Copy that took 24 hours was reduced to 4 hours by increasing DA buffers to 8 from 32.
o Memory used on the MA host• Block Size x DA Buffers x Concurrency
Data Protector Tape Backup Performance
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10 March 2009
Tuning for Performance (4)Data Protector Settings
Concurrencyo Specifies the number of Disk Agents writing simultaneously to a Media
Agent.o Range of 1-32, default is 4.o Has negative effect on restore performance when not doing complete
restore of the backup.o Keep to minimum needed for tape drive streaming.
Data Protector IDB logging levelo Limit logging to level required for restore.
Data Protector Tape Backup Performance
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10 March 2009
Tuning for Performance (5)Data Protector Settings
CRC checkingo More useful with older, less robust tape & drive technology.o Allows discovery of data corruption AFTER the backup, during Verify
or Restore.o High CPU usage.
• See “HP Data Protector software performance white paper” in Reference section:
In tests with LTO3, enabling CRC reduced backup performance by 20%.
Data Protector Tape Backup Performance
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10 March 2009
Tuning for Performance (6)Data Protector Settings
Software Compression o Helps with limited capacity LAN.o Except for LTO/Ultrium drives, disable hardware compression,
otherwise, drive performance will drop and data blocks will expand.• UNIX - device file• Windows - N at the end of the SCSI path specification
o High CPU• See “HP Data Protector software performance white paper” link, page 54,
in Reference section:Figure 36 shows that enabling the software compression increased the
CPU load from 13% to 99%. The CPU load was very high because Data Protector compressed five file systems in parallel.
Data Protector Tape Backup Performance
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10 March 2009
Tuning for Performance (7)Data Protector Settings
Set Object Order by SizeBackups typically run slower, often dramatically slower, near the end.o Concurrency effectively drops because there are no additional Disk Agents to
replace a completed Disk Agent so fewer and fewer Disk Agents are running.
o With reduced Concurrency, the data delivery rate drops below the drive’s minimum streaming rate. This causes a precipitous drop in performance.
o Rearrange the order in which Objects will be backed up so that Objects of about the same size are grouped together and backed up concurrently.
• On the Summary tab for a Backup Specification, or on the Summary page of the wizard for a new Backup Specification, change the Object order by right-click, “Move up” or “Move down”.
• The Objects stay listed in the same order but the new Object Order is shown on the far right, so either stretch the window or scroll right to see the ordering.
• The Object listing can be rearranged by clicking on the “Order” column heading.
Data Protector Tape Backup Performance
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10 March 2009
Advanced options
Tuning: Data Protector Tape Drive Options (1)
Settings
Devices & Media
256 KB for Ultrium 960 and newer.See “Whitepaper for the Ultrium 960”
in Reference section
Sizes
Data Protector Tape Backup Performance
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10 March 2009
Tuning: Data Protector Tape Drive Options (2)
CRC Check
Concurrencysetting
Advanced options
Devices & Media
Settings Settings
Data Protector Tape Backup Performance
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10 March 2009
REFERENCE
Data Protector Tape Backup Performance
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10 March 2009
No Compression
LTO/Ultrium-1 230 LTO/Ultrium-2 460 LTO/Ultrium-3 960 LTO/Ultrium-4 1840
15 MB/s Ultrium-1 media 30 MB/s Ultrium-2 media 80 MB/s Ultrium-3 media 120 MB/s Ultrium-4 media
~50 GB/hour ~100 GB/hour ~288 GB/hour ~430 GB/hour
15 MB/s Ultrium 1 media 30 MB/s Ultrium-2 media 80 MB/s Ultrium-3 media
20 MB/s Ultrium-1 media 30 MB/s Ultrium-2 media
2:1 Compression
LTO/Ultrium-1 230 LTO/Ultrium-2 460 LTO/Ultrium-3 960 LTO/Ultrium-4 1840
30 MB/s Ultrium-1 media 60 MB/s Ultrium-2 media 160 MB/s Ultrium-3 media 240 MB/s Ultrium-4 media
~100 GB/hour ~200 GB/hour ~576 GB/hour ~860 GB/hour
40 MB/s Ultrium-1 media 60 MB/s Ultrium-2 media 160 MB/s Ultrium-3 media
40 MB/s Ultrium-1 media 60 MB/s Ultrium-2 media
LTO/Ultrium Best Data Transfer Rates (1)
Data Protector Tape Backup Performance
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10 March 2009
4:1 Compression
LTO/Ultrium-1 230 LTO/Ultrium-2 460 LTO/Ultrium-3 960 LTO/Ultrium-4 1840
60 MB/s Ultrium-1 media 120 MB/s Ultrium-2 media 320 MB/s Ultrium-3 media 480 MB/s Ultrium-4 media
~200 GB/hour ~400 GB/hour ~1,152 GB/hour ~1,728 GB/hour
80 MB/s Ultrium 1 media 120 MB/s Ultrium-2 media 320 MB/s Ultrium-3 media
80 MB/s Ultrium-1 media 120 MB/s Ultrium-2 media
8:1 Compression
LTO/Ultrium-1 230 LTO/Ultrium-2 460 LTO/Ultrium-3 960 LTO/Ultrium-4 1840
120 MB/s Ultrium-1 media 240 MB/s Ultrium-2 media 640 MB/s Ultrium-3 media 960 MB/s Ultrium-4 media
~200 GB/hour ~800 GB/hour ~2,304 GB/hour ~3,456 GB/hour
160 MB/s Ultrium-1 media 240 MB/s Ultrium-2 media 640 MB/s Ultrium-3 media
160 MB/s Ultrium-1 media 240 MB/s Ultrium-2 media
LTO/Ultrium Best Data Transfer Rates (2)
Data Protector Tape Backup Performance
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10 March 2009
LTO/Ultrium-1 230 LTO/Ultrium-2 460 LTO/Ultrium-3 960 LTO/Ultrium-4 1840
No Compression
6-15 MB/s~20-50 GB/hour
10-30 MB/s~35-100 GB/hour
27-80 MB/s~95-288 GB/hour
40-120 MB/s~144-432 GB/hour
2:1 Compressed
12-30 MB/s~40-100 GB/hour
20-60 MB/s~70-200 GB/hour
54-160 MB/s~190-576 GB/hour
80-240 MB/s~288-864 GB/hour
4:1 Compressed
24-60 MB/s~80-200 GB/hour
40-120 MB/s~140-400 GB/hour
108-320 MB/s~380-1,152 GB/hour
160-480 MB/s~576-1,728 GB/hour
8:1 Compressed
48-120 MB/s~160-400 GB/hour
80-240 MB/s~280-800 GB/hour
216-640 MB/s~760-2,304 GB/hour
320-960 MB/s~1,152-3,456 GB/hour
LTO/Ultrium Data Rate Matching – Streaming Range
Assumes same generation cartridge
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LTO/Ultrium-1 230 LTO/Ultrium-2 460 LTO/Ultrium-3 960 LTO/Ultrium-4 1840
No Compression
100 GB 200 GB 400 GB 800 GB
2:1 Compression
200 GB 400 GB 800 GB 1.6 TB
4:1 Compression
400 GB 800 GB 1.6 TB 3.2 TB
8:1 Compression
800 GB 1.6 TB 3.2 TB 6.4 TB
Assumes same generation cartridge
These capacities apply for any streaming rate.
LTO/Ultrium Tape Capacity When Streaming End-to-End
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TYPICAL FILE COMPRESSION RATIOSData type Typical compression
CAD 3.8:1
Spreadsheet/word processing 2.5:1
Typical file/print server 2.0:1
Lotus Notes DB 1.6:1
Microsoft Exchange/SQL DB 1.4:1
Oracle/SAP DB 1.2:1
From: Enterprise Backup solution Design Guide (Ninth edition: February 2008), page 73
http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00775232/c00775232.pdf
NOTE: In limited sampling from customers, filesystem backups of Oracle databases compress 8:1 (probably due to unused blocks)! 8:1 requires VERY high data delivery rate to achieve streaming!
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Performance Analysis and Tuning (1)
Performance Topics in Data Protector’s Online Help• DP GUI, Help menu, Help Topics
• Contents tab• Expand “Backup” (click on [+])
• Expand”Backup Performance” (click on [+]) 16 Articles, some brief, some a bit old but valid
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Performance Analysis and Tuning (2)
HP Data Protector software performance white paper
http://h71028.www7.hp.com/ERC/downloads/4AA1-3836ENW.pdfo Page 4
• This white paper provides performance-related information for HP Data Protector software 6.0 together with some typical examples. The emphasis is on backup servers and two common backup and restore performance questions:
– Why are backups so slow?
– Why are restores so slow?
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Performance Analysis and Tuning (3)
Introduction to Performance Tuning for HP-UXUPERFKBAN00000726 (updated 2006)
http://saw.cce.hp.com/km/saw/view.do?docId=emr_na-c00958823
Troubleshooting Backup Performance - OVKBRC00006135 (updated 2004)
http://saw.cce.hp.com/km/saw/view.do?docId=ucr_na-KMNOVKBRC00006135
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Performance Analysis and Tuning (4)
Whitepaper for the Ultrium 960o Discusses performance issues.
http://h71028.www7.hp.com/ERC/downloads/5982-9971EN.pdfo Recommends 256 KB blocksize for Ultrium 960.o Data Protector default setting is 64 KB for Ultrium.o On Windows, for blocksize greater than 64 KB, MaximumSGList
registry entry for the HBA may need to be adjusted.
HP StorageWorks Enterprise Backup Solution design guideo Chapter 8 Performance: Finding bottlenecks
http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00775232/c00775232.pdf
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Analysis Tools (1)
PAT - Performance Analysis Tools
http://www.hp.com/support/pat
LTT - Library and Tape Tools
http://h18006.www1.hp.com/products/storageworks/ltt/index.html?jumpid=reg_R1002_USEN
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LTO / Ultrium (1)
LTO - Linear Tape-Open
http://en.wikipedia.org/wiki/Linear_Tape-Open
QuickSpecs HP StorageWorks Ultrium
http://h18006.www1.hp.com/products/quickspecs/11739_div/11739_div.pdf
“Testing LTO-3 vs. LTO-2 and SDLT”o InfoStor magazine article (2005)o Detailed discussion of testing and of performance factors.
http://www.infostor.com/article_display/testing-lto-3-vs-lto-2-and-sdlt/223974/s-articles/s-infostor/s-volume-9/s-issue-3/s-lab-review/s-1.html
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LTO / Ultrium (2)
Data Rate Matching
HP Ultrium tape drive, DRM - Data Rate Matching
http://www.sundds-lto.com/uploadLinks/DRM_Technical_Overview_LTO4.pdf
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LTO / Ultrium (3)
User Guide: HP StorageWorks Ultrium
http://bizsupport.austin.hp.com/bc/docs/support/SupportManual/c01141242/c01141242.pdf
Includes very basic performance guidance o Pages 58-59
Can your system deliver the required performance?
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LTO / Ultrium (4)
IBM: LTO: A better format for mid-range tape – great description of the robust Ultrium datablock designhttp://www.research.ibm.com/journal/rd/474/jaquette.html
HP StorageWorks Ultrium 960 tape drive technical white paperhttp://h71028.www7.hp.com/ERC/downloads/5983-0148EN.pdf
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Consulting - HP Services
HP Consultingo HP ValuPack Services
http://h20219.www2.hp.com/services/cache/109579-0-0-225-121.html#services
“HP Services Valupak Consulting”o 2-page brochure
ftp://ftp.hp.com/pub/services/perevent/valupack/vpbrochure.pdf
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