I have a short question:

On three servers i ran tsatest, some big difference where shown
although the type and number of data is about the same, all servers
are HP DL380 with 4Gb memory:

Server A:
Raw data MB/min: 1040
Effective MB/min: 290

Server B:
Raw data MB/min: 4600
Effective MB/min: 460

Server C:
Raw data MB/min: 830
Effective MB/min: 805

Can anyone explain why these difference do exist?