Intel 7xx Servers, 170 Servers, AS/400 RISC Server 100, Dasd and Backup Devices Sharing a Tower

15.11 DASD and Backup Devices Sharing a Tower

The system architecture does not require that DASD and backup devices be kept separated. Testing in the IBM Rochester Lab, we had attached one backup device to each tower and all towers had 45 DASD units in them, when we did the 3580 002 testing. The 3592J has similar characteristics to the 3580 002 but the 3580 003 and 3592E models have greater capacities which create new scenarios. You aren’t physically limited to putting one backup device in a tower, but for the newest high speed backup devices you can saturate the bus if you have multiple devices in a tower. You need to look at your total system or partition configuration in order to determine if it is possible to use multiple high speed devices on the system and still get the most out of these devices. No matter what you determine is possible we advocate spreading your backup devices amongst the towers available.

5 to 75 DASD Backup Operations
(Large File Workload) to Ultrium 3 Tape
500	520 2 way 16GB Memory	5 Dasd
400		10 Dasd
		15 Dasd
300		20 Dasd
		25 Dasd
GB/HR		30 Dasd
200		35 Dasd
100		40 Dasd
		45 Dasd
		50 Dasd
0		55 Dasd
	Restore	60 Dasd
Save
	Operation	75 Dasd

5 to 75 DASD Backup Operations

(User Mix Workload) to Ultrium 3 Tape

520 2 way 16GB Memory
200
150
GB/HR 100
50
0	Restore
Save
Operation
IBM i 6.1 Performance Capabilities Reference - January/April 2008

5 Dasd

10 Dasd

15 Dasd

20 Dasd

25 Dasd

30 Dasd

35 Dasd

40 Dasd

45 Dasd

50 Dasd

55 Dasd

60 Dasd

75 Dasd

© Copyright IBM Corp. 2008 Chapter 15. Save/Restore Performance 254