HP StoreOnce 4430 HP StoreOnce Backup System Concepts and Configuration Guidel - Page 21

Data compression and encryption backup application features

Get HP StoreOnce 4430 PDF manuals and user guides View all HP StoreOnce 4430 manuals
Add to My Manuals
Save this manual to your list of manuals

Page 21 highlights

we could configure 6 devices with say 17 streams to each or 20 devices with 5 streams to each. 6 devices is preferable because: • Less devices are easier to manage but we can still group similar data types into the same device • They provide best possible throughput when we have the higher stream count to a device Data compression and encryption backup application features Both software compression and encryption will randomize the source data and will, therefore, not result in a high deduplication ratio for these data sources. Consequently, performance will also suffer. The StoreOnce Backup system will compress the data at the end of deduplication processing anyway, before finally writing the data to disk. For these reasons it is best to do the following, if efficient deduplication and optimum performance are required: • Ensure that there is no encryption of data before it is sent to the StoreOnce appliance. • Ensure that software compression is turned off within the backup application. Not all data sources will result in high deduplication ratios; deduplication ratios are data type dependent, change rate dependent and retention period dependent. Deduplication performance can, therefore, vary across different data sources. Digital images, video, audio and compressed file archives will typically all yield low deduplication ratios. If this data predominantly comes from a small number of server sources, consider setting up a separate library/share/Catalyst store for these sources for better deduplication performance. In general, high- change rates yield low dedupe ratios, whilst low change rates yield high dedupe ratios over the same retention period. As you might expect - multiple full backups yield high dedeup ratios compared to Full and Incremental backup regimes. Backup Application considerations 21

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
we could configure 6 devices with say 17 streams to each or 20 devices with 5 streams to each.
6 devices is preferable because:
•
Less devices are easier to manage but we can still group similar data types into the same
device
•
They provide best possible throughput when we have the higher stream count to a device
Data compression and encryption backup application features
Both software compression and encryption will randomize the source data and will, therefore, not
result in a high deduplication ratio for these data sources. Consequently, performance will also
suffer. The StoreOnce Backup system will compress the data at the end of deduplication processing
anyway, before finally writing the data to disk.
For these reasons it is best to do the following, if efficient deduplication and optimum performance
are required:
•
Ensure that there is no encryption of data before it is sent to the StoreOnce appliance.
•
Ensure that software compression is turned off within the backup application. Not all data
sources will result in high deduplication ratios; deduplication ratios are data type dependent,
change rate dependent and retention period dependent. Deduplication performance can,
therefore, vary across different data sources. Digital images, video, audio and compressed
file archives will typically all yield low deduplication ratios. If this data predominantly comes
from a small number of server sources, consider setting up a separate library/share/Catalyst
store for these sources for better deduplication performance. In general, high- change rates
yield low dedupe ratios, whilst low change rates yield high dedupe ratios over the same
retention period. As you might expect – multiple full backups yield high dedeup ratios compared
to Full and Incremental backup regimes.
Backup Application considerations
21