Comparing IBM System i And System p

With increasingly shared hardware between iSeries and pSeries machines many of you are asking questions about how to compare performance.

IBM System p

Traditionally, IBM Unix used the ROLTP to compare performance. Due to huge performance increases in recent years, the ROLTP has been replaced with rPerf’s, where

1 rPerf = ~ 25 ROLTP

Remember though, that when you are using these comparisons, they can only be used as an estimate.

With IBM iSeries you can compare machines using CPW

You can use the formula:

1 rPerf = 612 cpw

There are many other comparisons which can also be used. If you would like to know more information, it’s probably worth visiting the Standard Performance Evaluation Corporation (SPEC) web site. You’ll find a range of comparisons including some that integrate hardware and software.

While all of these comparisons are just guidelines, they can be a great help to you if you are looking for an idea as to which machine you need to upgrade to.

If you’re not sure about how to undertake a comparison, please call Computer Merchants on 1800 777 111 and we’ll be happy to help you with any comparisons you need to make.