Intel AS/400 RISC Server - Manual (Page 247)

15.5 Lower Performing Backup Devices
With the lower performing backup devices, the devices themselves become the gating factor so the save
rates are approximately the same, regardless of system CPU size (DVD-RAM).
25% Source File / 1 Directory Many Objects / Many Directories Many Objects
55% User Mix / Domino / Network Storage Space
95% Large Database File
Amount of Loss Workload Type
Table 15.5.1 Lower performing backup devices LossFromWorkLoadType Approximations (Save Operations)
Example for a DVD-RAM:
DeviceSpeed * LossFromWorkLoad * Compaction Factor
0.75 * 0.95 = (.71) * 2.8 = (1.995) MB/S * 3600 = 7182 MB/HR = 7 GB/HR
0.75 * 0.95 = (.71) * No Compression * 3600 = 2556 MB/HR = 2.5 GB/HR
15.6 Medium & High Performing Backup Devices
Medium & high performing backup devices (SLR60, SLR100, VXA-2, VXA-320).
25% Source File / 1 Directory Many Objects / Many Directories Many Objects
65% User Mix / Domino / Network Storage Space
95% Large Database File
Amount of Loss Workload Type
Table 15.6.1 Medium performing backup devices LossFromWorkLoadType Approximations (Save Operations)
Example for SLR100:
DeviceSpeed * LossFromWorkLoad * Compaction Factor
5.0 * 0.95 = (4.75) * 2.0 = (9.5) MB/S * 3600 = 34200 MB/HR = 34 GB/HR
15.7 Ultra High Performing Backup Devices
High speed backup devices are designed to perform best on large files. The use of multiple high speed
backup devices concurrently or in parallel can also help to minimize system save times. See section on
Multiple backup devices for more information (3580 Ultrium-2, 3580 Ultrium-3 (2Gb & 4Gb Fiber
Channel), 3592J, 3592E).
5% Source File / 1 Directory Many Objects / Many Directories Many Objects
50% User Mix / Domino / Network Storage Space
95% Large Database File
Amount of Loss Workload Type
Table 15.7.1 Higher performing backup devices LossFromWorkLoadType Approximations (Save Operations)
Example for 3580 ULTRIUM-2 Fiber:
DeviceSpeed * LossFromWorkLoad * Compaction Factor
LG File 35.0 * 0.95 = (33.25) * 2.8= (93.1) MB/S *3600 = 335160 MB/HR = 335 GB/HR
UserMix 35.0 * 0.50 = (17.5) * 2.8= (49) MB/S *3600 = 176400 MB/HR = 176 GB/HR
Source 35.0 * 0.05 = (1.75) * 2.8= (4.9) MB/S *3600 = 17640 MB/HR = 17.6 GB/HR
NOTE: Actual performance is data dependent, these formulas are for estimating purposes and may
not match actual performance on customer systems.
IBM i 6.1 Performance Capabilities Reference - January/April/October 2008
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Copyright IBM Corp. 2008 Chapter 15. Save/Restore Performance 247