Disk Performance Improvement Through Transfer Rate Mismatch Compensation
Original Publication Date: 1988-May-01
Included in the Prior Art Database: 2005-Feb-15
Direct-access storage device controllers controlling multiple devices generally transfer data between the host and buffers in the controller at a rate several times faster than the data transfer rate between the devices and the buffers in the controller. The controller notifies the host when transfer between the host and the buffers in the controller may begin (attention). After a time during which the host connects (connection), the transfer begins. Because the controller-host transfer rate is greater than the device-controller transfer rate, the host transfer tends to catch up to the device transfer and thereafter either runs at the slower device-controller transfer rate or the host disconnects, does some other work, reconnects when again signaled by attention, and completes the transfer.