STORE and TurboSTORE/iX Products Manual (B5151-90003)

50 Chapter3

Preparing Storage Devices

Preparing Tape and DDS Devices

Figure 3-9. Parallel Backup

Currently, all STORE and TurboSTORE products support a maximum of 16 parallel

backup devices. The actual speed of performance depends on the system, disk

conﬁguration and the backup devices used.

When using a multiple-processor machine, you can see increased backup performance

when doing parallel backups. Each parallel device or device pool is controlled by a separate

process. Since each process can be run simultaneously on different processors, this will

improve your backup performance.

A general rule for doing multi-processor parallel backups is to use one less parallel set

than you have processors. For example, on a 4-way system, perform a 3-device parallel

backup. This is recommended because STORE uses two additional processes to control the

overall backup.

NOTE

Depending on your system conﬁguration and bandwidth, you should still see

increased backup performance using parallel devices, even if you use more

parallel devices than you have processors.

To store ﬁles to a set of four parallel devices, the following set of commands can be used:

:FILE PARA;DEV=7

:FILE PARB;DEV=8

:FILE PARC;DEV=9

:FILE PARD;DEV=11

:STORE @.OPERATOR.SYS;;&

:STORESET=(*PARA),(*PARB),(*PARC),(*PARD)