Monitoring poll threads with the onstat utility

While the database server is online, you cannot drop a CPU virtual processor that is running a poll thread. To identify poll threads that run on CPU virtual processors, use the following command:
onstat -g ath | grep 'cpu.*poll'
The following onstat -g ath output shows two CPU virtual processors with poll threads. In this situation, you cannot drop to fewer than two CPU virtual processors.
tid  tcb      rstcb  prty  status    vp-class  name

8     a362b90  0     2     running   1cpu      tlitcppoll
9     a36e8e0  0     2     cond wait arrived   3cpu 

The status field contains information, such as running, cond wait, IO Idle, IO Idle, sleeping secs: number_of_seconds, or sleeping forever. To improve performance, you can remove or reduce the number of threads that are identified as sleeping forever.

For more information on the types of virtual processors, see the chapter on virtual processors and threads in the IBM® Informix® Administrator's Guide.

This command has an equivalent SQL administration API function.

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