This is really interesting. Lots of clue on the subject helping conflict management on hosting application service…..
I and reader like me will really appreciate you if you show the script by which device names are relaced by the partition/logical volume name (more generic understanding).
Apart from this here is another puzzle..
Until recently I was wondering with a simple question but it seems the answer is pretty complex. The Question is something like…..
An application administrator before implementing the system goes to storage administrator (Lets assume it is real big storage …very big…) to allocate a chunk of TB (space /Lun/ Devices or) for his application to run. Now the application administrator feels doubt that the chunk allocated to him does not satisfy the IOPS hunger of the application. So he returns back to storage administrator and ask …Tell me what maximum IOPS possible in the storage chunks you allocated to me……The Storage administrator remain speech less…..How can he calculate the IOPS maximum possible to the storage chunks which is spread over multiple disk drives, some partially and some fully……..

Can you throw some light on it?


Dirty Cache

Does this story sound familiar?

The end users of a database application start complaining about poor system response and long running batch jobs. The DBA team starts investigating the problem. DBA’s look at their database tools such as Enterprise Manager, Automatic Workload Repository (AWR) reports, etc. They find that storage I/O response times are too high (such as an average of 50 milliseconds or more) and involve the storage team to resolve it.

The storage guys, in turn, look at their tooling – in case of EMC this could be Navisphere Analyzer, Symmetrix Performance Analyzer (SPA) or similar tools. They find completely normal response times – less than 10 milliseconds average.

The users still complain but the storage and database administrators point to each other to resolve the problem. There is no real progress in solving the problem though.

Two Way Communications

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