MDA_DEVICE_IO

Device I/O activity

ROWID

(INSTANCEID, LOGICALNAME)

Columns

Name Data Type Description
INSTANCEID long Instance ID; 0 = non-CE
READS double Number of reads
APFREADS double Number of asynchronous prefetch (APF) reads
WRITES double Number of writes
DEVSEMAPHOREREQUESTS double Number of I/O operations to mirrored device, if applicable
DEVSEMAPHOREWAITS double Number of waits for sync on I/O operation to mirrored device, if applicable
IOTIME double Duration of time, in milliseconds, waiting for I/O requests to be satisfied
LOGICALNAME string(32) Logical name for the device
PHYSICALNAME string(132) Full file path for the device
DEVICETYPE string(24) Type of device (Default Disk, Physical Disk, Dump Device)
MERGESTATUS long Internal-use merge status; created by Surveillance
READS_DELTA double Delta number of reads
READS_RATE double Number of reads per second, in interval
READS_RATE_MAX double Maximum number of reads per second, since collection started
READS_RATE_AVG double Average number of reads per second, since collection started
APFREADS_DELTA double Delta number of asynchronous prefetch (APF) reads
APFREADS_RATE double Number of asynchronous prefetch (APF) reads per second, in interval
APFREADS_RATE_MAX double Maximum number of asynchronous prefetch (APF) reads per second, since collection started
APFREADS_RATE_AVG double Average number of asynchronous prefetch (APF) reads per second, since collection started
WRITES_DELTA double Delta number of writes
WRITES_RATE double Number of writes per second, in interval
WRITES_RATE_MAX double Maximum number of writes per second, since collection started
WRITES_RATE_AVG double Average number of writes per second, since collection started
IO_DELTA double Delta number of I/O operations (reads + APF reads + writes)
IO_RATE double Number of I/O operations per second, in interval
IO_RATE_MAX double Maximum number of I/O operations per second, since collection started
IO_RATE_AVG double Average number of I/O operations per second, since collection started
DEVSEMAPHOREREQUESTS_DELTA double Delta number of I/O operations to mirrored device, if applicable
DEVSEMAPHOREREQUESTS_TOTAL double Total number of I/O operations to mirrored device, if applicable, since collection started
DEVSEMAPHOREWAITS_DELTA double Delta number of waits for sync on I/O operation to mirrored device, if applicable
DEVSEMAPHOREWAITS_TOTAL double Total number of waits for sync on I/O operation to mirrored device, if applicable, since collection started
TIMEPERIOMS double Duration time, in milliseconds, per I/O operation in interval (IOTIME_DELTA / IO_DELTA)
TIMEPERIOMS_MAX double Maximum duration time, in milliseconds, per I/O operation in interval
TIMEPERIOMS_AVG double Average duration time, in milliseconds, per I/O operation in interval
READS_OVERALL double Total number of reads, since collection started
APFREADS_OVERALL double Total number of asynchronous prefetch (APF) reads, since collection started
WRITES_OVERALL double Total number of writes, since collection started
IO_PCT_TOTAL_AVG double % of total average number of I/O operations per second, since collection started (IO_RATE_AVG), over all devices
IO_PCT_TOTAL double % of total number of I/O operations per second, in interval (IO_RATE), over all devices

Requirements

Attributes: MDA
Minimum database version: 12.5.0.3