Perm Space Calculation using Space Management Portlet Viewpoint

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Perm Space Calculation using Space Management Portlet Viewpoint

There is a space management portlet in viewpoint and if we check space utilization by database it shows on 2 nodes system current perm = 1 TB and max perm 10 TB which is max perm of only 1st node but the same view when we show space amp wise it shows current perm the same 1 TB but max perm is 20 TB that means it is showing max_perm of both of the nodes. How tables are distributed on multiple nodes and why it is showing difference in max_perm in amp wise and database wise view ?

1 REPLY
Senior Apprentice

Re: Perm Space Calculation using Space Management Portlet Viewpoint

Hi,

 

By default (and certainly before TD 16.10) tables are distributed across all AMPs in the system. If you've got a 2 node system then you'll probably have 60 - 80 AMPs on the system, 30-40 on each Node.

 

The MaxPerm figures for a database are recorded in multiple places and you have to 'read them correctly' to understand them. Although to be fair your initial description sounds like it might be a big in VP.

 

Try the following SQL to see what is happening on your system.

select sum(maxperm) as spacelimit_sys
     ,max(maxperm) as spacelimit_amp
from dbc.diskspacev
where databasename = 'workdb';

FYI - this does not account for the TD 16.0 Global Space Accounting feature either, but let's start simple.

 

The space limit on a Node is simply the 'spacelimit_amp' * number of AMPs on a Node.

 

See what you get from that and then we can go from there.

 

Also, what release of TD are you using?

select *
from dbc.dbcinfov;

Cheers,

Dave

 

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