CN102436352A

CN102436352A - Method for increasing NCQ (Native Command Queuing) efficiency of SATA (Serial Advanced Technology Attachment) interface of SSD (Solid State Drive)

Info

Publication number: CN102436352A
Application number: CN201110250022XA
Authority: CN
Inventors: 姜凯; 于治楼; 梁智豪
Original assignee: Inspur Electronic Information Industry Co Ltd
Current assignee: Inspur Electronic Information Industry Co Ltd
Priority date: 2011-08-29
Filing date: 2011-08-29
Publication date: 2012-05-02

Abstract

The invention provides a method for increasing the NCQ (Native Command Queuing) efficiency of an SATA (Serial Advanced Technology Attachment) interface of an SSD (Solid State Drive), belonging to the technical field of micro-electronics. The method comprises the following steps of: finally executing a write instruction in instructions in a command queue according to different speeds of read and write; analyzing the correlation of the instructions, placing the instructions with the correlation together and executing according to an instruction press-in sequence and then placing the instructions without correlation together and executing according to the sequence; and executing the instructions with the correlation before the instructions without the correlation. Compared with the prior art, the method disclosed by the invention has increased read-write efficiency of the SSD.

Description

A kind of method that improves the SATA interface NCQ efficient of SSD

Technical field

The present invention relates to microelectronics technology, specifically a kind of method that improves the SATA interface NCQ efficient of SSD.

Background technology

SSD is because its storage medium is NandFlash, so it has just had similar advantage with NandFlash: light, storage density is big, low in energy consumption, antidetonation and temperature adaptation wide ranges.And that the SATA interface has transmission speed is fast, self has CRC check, has very high data transmission accuracy, supports hot plug, has therefore occupied most markets of memory device.

The SSD of SATA interface proportion in solid-state storage is very big, and NCQ is designed to improve the performance of hard disk under the load condition that increases day by day and the technology of stability.Send many hard disks that instruct the user when application program of user, the NCQ hard disk can be optimized the order of accomplishing these instructions, reaches the purpose that promotes performance thereby reduce mechanical load.The NCQ technology is a kind of inner optimization work load of hard disk execution sequence that makes, and realizes the intelligent data management through the order in the internal queues is resequenced, and improves the various performance restrictions that hard disk receives because of mechanical part.But this is obviously for the solid state hard disc that does not have mechanical part (SSD) and be not suitable for, and therefore, proposes the NCQ mechanism of a kind of suitable SSD, can have very great help for improving the SSD read-write efficiency.

Summary of the invention

The method that the purpose of this invention is to provide the SATA interface NCQ efficient of a kind of SSD of raising.

The objective of the invention is to realize that the speed according to read and write is different earlier with instruction in the command queue (Command Queue), is placed on last execution writing to instruct by following mode; The order that is pressed into according to instruction again, the correlativity of analysis instruction is put the instruction with correlativity and according to being pressed into the order execution, putting the instruction that does not have correlativity together and carry out in proper order together; Carry out before being placed on instruction the instruction that does not have correlativity with correlativity.

The instruction of correlativity is meant the instruction that writes and read identical address or read identical data.

The present invention compares with prior art, utilizes the characteristics that the NCQ of SATA can out of order execution command, according to the characteristics of Nandflash self, arranges the instruction sequences among the Queue again, makes the SATA instruction carry out to such an extent that efficient is improved.

Description of drawings

Accompanying drawing 1 is a work system structured flowchart of the present invention.

Embodiment

Detailed explanation below below in conjunction with accompanying drawing a kind of method of the SATA interface NCQ efficient that improves SSD being done.

Speed according to read and write is different earlier with the instruction in the command queue (Command Queue), is placed on last execution writing instruction; The order that is pressed into according to instruction again, the correlativity of analysis instruction is put the instruction with correlativity and according to being pressed into the order execution, putting the instruction that does not have correlativity together and carry out in proper order together; Carry out before being placed on instruction the instruction that does not have correlativity with correlativity.The instruction of correlativity is meant the instruction that writes and read identical address or read identical data.

Workflow is that the SATA instruction is pressed into instruction in the command queue (Queue) through the command analysis device; For example, system has 8 passages, and each passage has an independently Queue; Once can be pressed into maximum 12 instructions among the Queue, be respectively cmd0 to cmdb.Instruction is mainly reads or writes.The order that method is pressed into according to instruction earlier, whether analysis instructs has correlativity, like cmd0 and cmd2, be respectively the data that write and read identical address, but cmd0 is pressed into Queue earlier, so the sequencing of cmd0 and cmd2 is that cmd0 is preceding.Because after cmd0 was finished, the data that write so can data directly be read, and did not need from Nandflash, to read also in buffer again, therefore, cmd2 is adjusted to after the cmd0, before the cmd1.Cmd7 and cmd9 are similarly and read identical data, and the data that also have no between them change, therefore, and cmd7 and the cmd9 execution of will putting together.Other instruction does not have correlativity again, and therefore, cmd3 and cmd6 are for writing instruction, and speed is slow, so be placed on the last of Queue, other read instruction and are placed on before them.The adjustment of instruction sequences among the Queue finishes like this, and order is carried out afterwards.

The present invention compares with prior art, utilizes the characteristics that the NCQ of SATA can out of order execution command, according to the characteristics of Nandflash self; Again arrange the instruction sequences among the Queue; Make the SATA instruction carry out to such an extent that efficient is improved, thereby, have good value for applications.

Except that the described technical characterictic of instructions, be the known technology of those skilled in the art.

Claims

1. a method that improves the SATA interface NCQ efficient of SSD is characterized in that the speed according to read and write is different earlier with the instruction in the command queue (Command Queue), is placed on last execution writing instruction; The order that is pressed into according to instruction again, the correlativity of analysis instruction is put the instruction with correlativity and according to being pressed into the order execution, putting the instruction that does not have correlativity together and carry out in proper order together; Carry out before being placed on instruction the instruction that does not have correlativity with correlativity.

2. method according to claim 1 is characterized in that the instruction of correlativity is meant the instruction that writes and read identical address or read identical data.