How to find number of amp in the system?

Number of AMP depends on number of node in the system and  can vary from 8 to 40 depending on type of node used in system, latest node type 6690 can have 40 AMP on it.

Total AMP in the system can be found out by query

select hashamp() +1;

or 

select Vproc from dbc.Acctg where VprocType='AMP' group by Vproc;

It is recomended to have nodetype same accross the system to avoid any skew while processing request, but in case you have more than one node type in the system we can use below query to get nodewise number of AMPs in the system.

Select nodeid,count(distinct Vproc) from dbc.ResCpuUsageByAmpView group by 1

We can query to find what are the different node types are being used in the system

select distinct nodetype from  dbc.resusagespma;

Number of node in the system can be found out by

Select count(distinct nodeid) from dbc.resusagescpu;