How is sar -d aveq calculated

[Rebecca Callan]

Hi,

I am just wondering if anyone knows how sar calculates the average queue on the disk.

I know sun calculates it by
queue length * time on queue / disk busy time

sar output on HP seems to be a bit different to this. Does anyone know what algorithm it uses? Any help would be appreciated,

Rebecca

[Vincenzo Restuccia]

Report activity for each block device, e.g., disk or tape drive. One line is printed for each device that had activity during the last interval. If no devices were active, a blank line is printed. Each line contains the following data: device Logical name of the device and its corresponding instance. Devices are categorized into the following four device types:
disk1 - HP-IB disks (CS/80)
disk2 - CIO HP-FL disks (CS/80)
disk3 - SCSI and NIO FL disks
sdisk - SCSI disks;

%busy Portion of time device was busy servicing a request;
avque Average number of requests outstanding for the device;
r+w/s Number of data transfers per second (read and writes) from and to the device;
blks/s Number of bytes transferred (in 512-byte units) from and to the device;
avwait Average time (in milliseconds) that transfer requests waited idly on queue for the device;
avserv Average time (in milliseconds) to service each transfer request (includes seek, rotational latency, and data transfer times) for the device