Topic
2 replies Latest Post - ‏2014-05-16T16:34:53Z by chriscanto
T_IBM2002
T_IBM2002
2 Posts
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Pinned topic SVC 6.4 Too Many Mdisk Groups - How to Consolidate

‏2014-05-16T04:20:02Z |

Hello All,

Inhertied an SVC with 18 mdisk groups. Of course TPC health checks are complaining that >5 MDG are against

best practice due to the way SVC partitions cache.  Customer is not yet experiencing issues but would like

consolidate these groups down to 5 before they do.  Any ideas how this can be done more efficiently than vdisk migrations?

Thank you!

  • TMasteen
    TMasteen
    279 Posts
    ACCEPTED ANSWER

    Re: SVC 6.4 Too Many Mdisk Groups - How to Consolidate

    ‏2014-05-16T10:59:01Z  in response to T_IBM2002

    I suppose the 18 mdiskgroups are there for a reason. Maybe there are multiple backend storage devices having different kind of drives (speed\size\etc).
    If this is the case I would not just "merge" the different mdiskgroups.
    Dont understand why vdisk migration is not efficient.. multiple migrations can be done concurrent and migration speed can be adjusted.
     

  • chriscanto
    chriscanto
    271 Posts
    ACCEPTED ANSWER

    Re: SVC 6.4 Too Many Mdisk Groups - How to Consolidate

    ‏2014-05-16T16:34:53Z  in response to T_IBM2002

    I'd question the validity of that healthcheck item.  I don't think anyone should be thinking about more than five storage pools being a generically "bad thing".  It's just a case of understanding why you're putting storage into different pools and creating a sensible configuration for your individual requirements.

    The current SVC/Storwize cache partitioning behaviour is explained in at least one redbook, so I'd start there to see what you think.