When examining the processes running on an NT machine supporting Oracle, the major background Oracle process seen is oracle.exe. This multithreaded process contains everything that makes up the Instance set. DBWR, LGWR, PMON, SMON and so on. In Unix, these are distinct processes visible at the shell level; therefore their resource utilization may be seen by using acctcom and ps. In NT, using say Task Manager whatever the individual items are doing to the system is shown as being caused by oracle.exe. Most people trying to understand a bit more about operating system resource use by particular parts of the Oracle Instance will usually stop at this point.

However, Windows allows the user to examine the resource utilization of threads via the Performance Monitor in the same way as processes. The Oracle threads are named oracle/1, oracle/2 where the individual thread is identified to the user by a number. To decode this number into the actual activity name, running this sql:

select b.name, p.spid, p.pid
from v$bgprocess b, v$process p
where b.paddr = p.addr

to produce output like so:

will allow the PID to identify each individual thread. Using this, the resource utilization of each part of the Instance process set may be examined in the same way that they may be on Unix systems.