Administering and Monitoring Analysis Services - SQL Server Analysis Services 2012 Cube Development - page 283

You can query $system.DISCOVER_PERFORMANCE_COUNTERS to obtain the cur-
rent value of a specific performance counter, for example:
SELECT * FROM SYSTEMRESTRICTSCHEMA(
$SYSTEM.DISCOVER_PERFORMANCE_COUNTERS,
PERF_COUNTER_NAME =
'\MSOLAP$SQL2012:Threads\Processing Pool Busy
I/O job Threads')
There's more...
As you learned in this section, DMVs contain a lot of useful information about
SSAS metadata and internals even though the product does not have any system
databases. Please reference product documentation for the full list of DMVs at ht-
tp://msdn.microsoft.com/en-us/library/hh230820.aspx .