QDIO

QDIO Analysis

Specifics - QDIO utilization analysis:

QDIO is a highly efficient data transfer architecture in TCPIP. The ESAQDIO screen/report shows three formats that utilize QDIO - QDIO (an OSA adapter coded as OSD in the hardware), FCP (a SCSI interface protocol using an underlying Fibre Channel connection) or Hipersockets, also called internal QDIO, (a high-speed TCPIP connectivity within a CEC). ESAQDIO also shows VSWITCH activity, which is a virtual switch that connects networks. Usually a VSWITCH will be defined in z/VM with VSW in the name.

ESAQDIO - Shows Queued Input/Output (QDIO) activity for each QDIO device. Both the screen and report samples:

Device Number - This is the real QDIO device number.

Owner - This is the userid of the owner of the device.

QDIO Fmt - This is the format of the device - QDIO, FCP or Hipersocket.

Throughput/sec - This is the throughput in Buffers and Bytes that have been sent to or taken from the adapter. This is another area that knowing the typical rate is help to recognize when that rate is higher than normal, which could signify a problem or a network overrun.

ESAVSW - Shows virtual switch activity. Helpful network information:

Dev No. - This is the device number of the virtual switch (vswitch).

Control Userid - This is the virtual machine that is controlling the virtual switch.

Bytes/Second Recvd Sent - This is the total number of bytes received and sent per second. Look for large fluctuations.

Buffers/Second Overflows - This shows the number of input/output queue overflows per second. Look for overflows.

Packet Errors/Sec - This shows the packet errors per second (discarded and packets in error). Look for errors.

Switch name - This is the name of the virtual switch.

SCSI Device Data - Use several screens/reports to show device relationship