>> Yes, we have dedicate vdisks for metadata, but they are in the same
declustered arrays/recoverygroups, so they whare the same spindles
Thats imho not a good approach. Metadata operation are small and
random, data io is large and streaming.
Just think you have a highway full of large trucks and you try to get
with a high speed bike to your destination. You will be blocked.
The same problem you have at your destiation. If many large trucks
would like to get their stuff off there is no time for somebody with a
small parcel.
Thats the same reason why you should not access tape storage and disk
storage via the same FC adapter. ( Streaming IO version v.
random/small IO )
So even without your current problem and motivation for measureing i
would strongly suggest to have at least dediacted SSD for metadata and
if possible even dedicated NSD server for the metadata.
Meaning have a dedicated path for your data and a dedicated path for
your metadata.
All from a users point of view
Hajo
That's where i was puzzled too. GSS its a gpfs appliance and came
configured this way. Also official GSS documentation suggest to create
separate vdisks for data and meatadata, but in the same declustered
arrays. I always felt this a strange choice, specially if we consider
that metadata require a very small abbount of space, so few ssd could do
the trick....
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