Re: STRASPBAL on guested partitions

Sometimes I wonder if a little knowledge of how Linux on Power works would
help to understand this. We used to use Guested Linux. (Now we use
dedicated lpars.) One guested lpar had numerous virtual disks (it was
growing by leaps and bounds). There was some reason why we went through a
lot of effort to reduce the number (wasn't my task).

With a guested lpar, if your host has 90 disk arms, I would think that
your guest could then potentially share all 90 arms (depending on how
single level store scatters the data). Versus a dedicated partition that
has to have a section carved out with x number of arms, controllers, etc.

I don't know how multiple versus a single virtual disk plays into this. I
was rather hoping that it wasn't a performance concern one way or the
other. Hoping that all that would have been simply dumped onto the
hosting machine.

Granted, if STRASPBAL *USAGE is ignored by a guested lpar than what
happens when run on the hosting lpar? For instance, let's say file XYZ on
GUEST is heavily used. Now let's say you have two virtual disks
associated with GUEST. So when you run STRASPBAL *USAGE on HOST how would
it know that file XYZ on GUEST is heavily used? It wouldn't. What it may
know is that
/QFPNWSSTG/GDISTG01
or
/QFPNWSSTG/GDISTG02
or both, is heavily used and scatter that around?

Rob Berendt