I/O instruction scheduling method and device based on disk device attributes

Abstract

The invention provides an I / O (Input / Output) instruction scheduling method and an I / O instruction scheduling device based on attributes of disk equipment, which are used for realizing I / O instructionscheduling in a disk array system. The method comprises the steps of reading an I / O instruction from a memory, and adding the I / O instruction into a command queue corresponding to a target disk according to a target disk device ID of the I / O instruction; selecting a first disk device to be accessed through polling a plurality of disk devices; selecting a first physical channel in an idle state bypolling the plurality of physical channels; obtaining an I / O instruction from a command queue corresponding to the first disk device, and distributing the obtained I / O instruction to the first physical channel.

Description

Technical field [0001] The present invention belongs to the field of disk array readout, and in particular, the I / O instruction scheduling method and apparatus for disk device attributes. Background technique [0002] The storage system is an infrastructure that satisfies a large amount of data to read and write needs. Its input / output (I / O) performance directly determines the data read and write efficiency, which is a key factor affecting the overall performance of data. In a server storage array system, there may be thousands of different types of hard drives, such as SAS (Serial AttachedSCSI) Solid Masses, SAS Machine, SATA (Serial Attachment) Machinery, etc. To manage these types of hard drives, server hosts and hard disks typically include a hardware and software system called HBA (Host Bus Adapter) / RAID (RedundantArray Os Independent Disks) card, if there is more hard drive, there may also include expand boards ( Expander, its main architecture is shown figure 1 In...

AI Technical Summary

Problems solved by technology

[0010] 1. When the following conditions exist, all physical links may be waiting for the target disk, resulting in low utilization of the physical link: a) Multiple I / O instructions in succession access the same target disk, which is a more common occurrence

However, in fact, a disk can only establish one physical channel at a time. At this time, the command execution state machine may try to establish a link from multiple physical channels. Unsuccessful and invalid link establishment operations reduce the utilization rate of the link.

b) There are multiple I / O commands accessing the same target disk in a short period of time. If some I / O commands access a large amount of data, or the response speed of the target disk is slow, resulting in a long I / O command response time, there will also be Link establishment is unsuccessful and link utilization is lost

[0011] 2. It may cause some disks to be unavailable for a long time, that is, the disk access load is unbalanced

When the I / O command of a certain disk is at the end of the I / O queue, and there are many pending commands of other disks in front of the I / O queue, it needs to wait for the previous command to be executed before it can be executed, and the response speed of the disk There are inherent differences, and the response speed is much slower than the system speed. If the disk load is unbalanced, the slow response disk may occupy the link for a long time, which is not conducive to the efficient utilization of the physical link

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