Detail VMX Device Utilization Report (by Device)
Detail VMX Device Utilization Report (by device) report produces a tabular listing of activity for selected devices for the duration of the period specified in the run-time execution parameters.
micsrm140cd
The devices reported are selectable using run-time parameters based on device number, VOLSER, device class, or device type. The selection criteria are combined to produce "or" logic so that if device number 3FA is requested and device type 3380 is requested, all 3380 devices will be reported and device number 3FA will be reported whether it is a 3380 or not.
Intended use
Allows analysis of device activity over time, including such items as I/O activity, I/O queuing measures, and minidisks allocated. This report can be used to detect anomalies in the activity on a device that might be a cause of poor system response time.
Format
A tabular report in TIME order where each row represents a different measurement interval for the device:
I/O COUNT
The number of I/O operations performed by the device over the reporting interval.
%BUSY
The average utilization for the device over the interval.
CONNECT
The device connect time (the time that the device was connected to the channel to transfer data) expressed in seconds.
DISCONNECT
The device disconnect time (the time that the device was disconnected from the channel to prepare for data transfer) expressed in seconds.
PENDING
the device function pending time (the time between the initiation of a start operation and the execution of the first command in the channel program) expressed in seconds.
ACTONLY
the device-active-only time (the time that the subchannel is device-active but not subchannel active at the end of an I/O operation or chain of I/O operations initiated by START SUBCHANNEL) expressed in seconds.
RESPONSE TIME
The average number of milliseconds required for an I/O operation to complete.
I/Os QUEUED
The average number of operations queued by VM for the device.
MINIDISKS ALLOCATED
the number of minidisks that are allocated on the device (for DASD). This is equal to the number of minidisks in use on the volume plus links to those minidisks. For example, MAINT 190 may represent 100 allocations if 100 logged on users are linked to that minidisk.
An example of this report is provided in the Detail VMX Device Utilization Report (by device) figure.
Inquiry ID
- Tabular Report: VMXTXA
Data Source (File/Timespan):
VMXXDV01 - DETAIL
Data elements used
- VOLSER
- Volume Serial Number
- VMXDVDEV
- Device Number
- DEVTYPE
- Device Type
- DEVCLASS
- Device Class
- XDVAVSSC
- Average Start Subchannel Count
- XDVPCBSY
- Device Percent Busy
- XDVAVDCN
- Average Device Connect Time
- XDVAVDDC
- Average Device Disconnect Time
- XDVAVFPN
- Average Device Function Pending Time
- XDVAVDAO
- Average Device-Active-Only Time
- XDVAVRES
- Average Device Response Time
- XDVAVQUE
- Average I/Os Queued
- XDVAVMDA
- Average Minidisks Allocated
Calculations
The detail data is summarized using standard
MICS
summarization to the reporting interval specified with the run-time parameters.Usage considerations
None
Detail VMX Device Utilization Report (by device) Sample
+-------------------------------------------------------------------------------------------------------------------------+ | Device Utilization | |MICSI/S MANAGEMENT APPLICATIONS DEVELOPMENT | | | |INQUIRY: VMXTXA RUN DATE: 18JUNyy | | System: VM02 Date: Wednesday, May 26, yyyy | | Device Class: DASD/CKD Device Type: 3380K Volume: SYSTY9 Device Number: 0130 | |------------------------------------------------------------------------------------------------------------------------ | | I/O Device Response Time I/Os Minidisk | | Time Count %Busy Connect Disconnect Pending ActOnly (MSEC) Queued Allocated | |------------------------------------------------------------------------------------------------------------------------ | | 10:15 0 0.11 0.004 0.001 0.012 0.000 3.37 0 2 | | 10:30 0 0.15 0.015 0.002 0.004 0.000 83.86 0 2 | | 10:45 0 0.15 0.002 0.000 0.021 0.000 2.05 0 2 | | 14:15 0 0.04 0.002 0.000 0.005 0.000 2.09 0 2 | | 14:30 0 0.03 0.002 0.000 0.003 0.000 2.05 0 2 | | 14:45 0 0.04 0.002 0.000 0.003 0.000 2.53 0 2 | | | | | | | | | +-------------------------------------------------------------------------------------------------------------------------+