TW201835774A - Method for controlling the writing flow of a solid state disk - Google Patents

Abstract

The present invention is to disclose a method for controlling the writing flow of a solid state drive. The method reduces the writing flow of inner data when concurrently writing user data and inner data, and learns a delay time from the writing flow of user data at concurrency stage when the inner data have been written. The method reduces the writing flow of the user data with the delay time to stabilize the writing efficiency.

Description

 Solid state hard disk control method for writing traffic  

The present invention relates to a solid state hard disk, and more particularly to a method for controlling write traffic by a solid state hard disk for stabilizing the performance of writing data to a host.

Solid State Drive (SSD) is a single storage device that is integrated into a NAND Flash Memory Array. Because the flash memory erases the unit with the data block as the data, the data block contains the valid data page and the discarded invalid data page, and the excessive invalid data page occupies the effective storage space of the flash memory. Therefore, the solid state hard disk uses the Garbage Collection (GC) to recover the data blocks whose invalid data pages exceed the threshold, and the valid data pages in the data block are read and then moved to the blank data block. Then, erase the data of the entire recycling data block to form an alternate blank data block for the solid state hard disk to access the data.

As shown in FIG. 6, the buffer memory 1 of the prior art solid state hard disk includes, in addition to the user data (User Data) 2 of the temporary receiving host, the valid data that needs to be written back by the garbage collection mechanism, and the need The backed up logical entity comparison table and other internal data 3 need to be sequentially written into the flash memory array 4 by the data stream of the first in first out (FIFO) of each flash memory. In order to avoid affecting the writing performance of the user data 2 in the buffer memory 1, the prior art solid state hard disk usually writes the internal data 3 to the flash memory array 4 by using the space written by the user data. However, when writing internal data 3, the host often instructs the solid state hard disk to access the user data 2. If there is not much internal data written, the solid state hard disk can respond to the host's instructions in time without affecting the access performance of the user data 2. Once the internal data 3 is written too much, the solid state hard disk takes a long time to write to the internal data 3, and cannot respond to the host's instructions. The access performance of the host user data 2 is seriously affected, and even the access performance is reduced to Zero, causing the user to wait for a long time or empty.

Therefore, in addition to the prior art solid state hard disk, the internal data 3 and the user data 2 are simultaneously written into the flash memory array 1. Although the access performance of User Data 3 and the write performance of Internal Data 2 will be affected, the access performance of User Data 3 can be maintained at a certain level, and the access performance of User Data 3 can be prevented from being reduced to Zero, let the user feel like no space, to avoid the user's impression of low-performance solid-state hard disk.

However, in the foregoing prior art solid state hard disk, when the internal data and the user data are simultaneously written, as shown in FIG. 7, the access performance curve P of the user data is displayed, and the internal data and the user data are accessed simultaneously. During the writing period A, the solid state hard disk must share the control processing capability to write internal data, and the performance of the user data is reduced due to the crowding, and the performance curve is violently up and down. After the internal data is written, only the individual write period B of the user data is written, and the access performance is increased because there is no internal data write interference, and the same access performance level cannot be maintained in the before and after periods, and The write time period B is written into the user data in a short time, causing the user data to be crowded and squeezed, so that the performance curve has a long and downward shadow line L, and the same access performance level cannot be maintained. Therefore, there is still a problem in the control method of the write capacity of the solid state hard disk.

The object of the present invention is to provide a method for controlling write traffic by a solid state hard disk, which can reduce the write flow of internal data and increase the write flow of internal data by increasing the write time of internal data and user data. Data is written to the traffic to improve user data write performance.

Another object of the present invention is to provide a method for controlling write traffic by a solid state hard disk, which utilizes a write traffic for learning user data during a simultaneous write period to form a delay time, and writes the user with a delay time delay in a separate write period. Data, reducing the write traffic of user data to stabilize the write performance of user data.

In order to achieve the object of the foregoing invention, the method for controlling write traffic of the solid state hard disk of the present invention firstly controls to reduce the write traffic of the internal data, and the internal data includes a backup of the logical entity comparison table or a valid data page of the garbage collection data block, and then At the same time, the user data and internal data are written at the same time, and when the internal data is not completed, the user data and internal data are simultaneously written. When checking that the internal data has been written, the user data of the simultaneous writing period is written into the traffic learning delay time, and in the separate writing period, the delay time control is used to reduce the writing traffic of the user data.

The solid-state hard disk of the invention controls the method of writing the traffic, increases the writing time of the internal data to a preset extended writing time, or intermittently writes the internal data by using a fixed or unfixed interval time, so that the internal data is The write is completed by a preset extended write time to reduce the write flow of internal data. During the simultaneous writing period, the extended writing time of the internal data and the written data amount of the user data are recorded, and the writing data amount is divided by the extended writing time, and the writing traffic of the user data in the simultaneous writing period is calculated. . Then, the amount of data written in the user data of the time period is separately written, divided by the write traffic of the user data in the simultaneous writing period, and the delay time is learned.

The solid-state hard disk of the present invention controls the method of writing traffic, and uses the delay time to extend the writing time of the user data, or uses a fixed or unfixed interval time to intermittently write the user data, so that the user data is delayed. Write is completed to reduce the write traffic of user data.

10‧‧‧Electronic device storage system

11‧‧‧Host

12‧‧‧Central processor

13‧‧‧Dynamic random memory

14‧‧‧Transport interface

15‧‧‧ Solid State Drive

16‧‧‧ Controller

17‧‧‧ Buffer memory

18‧‧‧Flash Memory Array

20‧‧‧ User data

21‧‧‧ Internal information

A‧‧‧ simultaneous writing period

B‧‧‧Single writing period

T1‧‧‧ write time

T2‧‧‧Extended write time

T3‧‧‧Delayed time

1 is a functional block diagram of an electronic device storage system of the present invention.

Figure 2 is a schematic diagram of the solid state hard disk writing data of the present invention.

FIG. 3 is a graph showing the access performance of the user data of the present invention.

FIG. 4 is a schematic diagram of a solid state hard disk write data according to another embodiment of the present invention.

FIG. 5 is a flow chart of a method for controlling write traffic by a solid state hard disk according to the present invention.

Figure 6 is a schematic diagram of prior art solid state hard disk write data.

Figure 7 is a graph of the access performance of prior art user data.

The technical means and the efficacies of the present invention for achieving the above objects are as follows, and the preferred embodiments are described below with reference to the drawings.

Please refer to FIG. 1 to FIG. 3 . FIG. 1 is a functional block diagram of a storage system of an electronic device according to the present invention. FIG. 2 is a schematic diagram of data written by a solid state hard disk according to the present invention, and FIG. 3 is an access performance of user data according to the present invention. Graph. In FIG. 1, the electronic device storage system 10 of the present invention has a central processing unit (CPU) 12 and a dynamic random access memory (DRAM) 13 in the host 11, and a user to be written by the central processing unit 12 in conjunction with the dynamic random memory 13. The data 20 (see FIG. 2) is transmitted to a solid state hard disk (SSD) 15 connected to the transmission interface 14, and the controller 16 and the buffer memory 17 are disposed in the solid state hard disk 15. The controller 16 cooperates with the buffer memory 17 to receive the host. 11 User data 20 to be written, the user data 20 is temporarily stored in the buffer memory 17 to be written to the flash memory array 18.

In order to manage the relative relationship between the logical address of the data and the physical address stored in the flash memory array 18, the solid state hard disk 15 first reads the management data of each data block in the flash memory array 18 at startup. A logical entity comparison table of logical addresses and physical addresses forming the data is stored in the buffer memory 17. In order to prevent the memory data of the logical entity table from disappearing when the volatile buffer memory 17 is powered off, the logical entity comparison table is periodically written into the non-volatile flash memory array 18 for backup.

In addition, the solid state hard disk 15 uses the garbage collection mechanism to read out the valid data pages in the data block to the buffer memory 17 for the data block with too many invalid data pages in the flash memory array 18 to be written. The data is moved to the spare blank data block of the flash memory array 18 to recover the data block. Therefore, the solid state hard disk 15 mainly needs to process the internal data 21 of the solid state hard disk 15 itself (see FIG. 2) in addition to the user data 20 written to the host computer, and the internal data 21 includes the foregoing written logical entity comparison table backup and garbage. The valid data page of the data block is recovered, and the data temporarily stored in the buffer memory 17 is sequentially written into the flash memory array 18 by the FIFO data pipes.

As shown in FIG. 2, since the controller 16 of the solid state hard disk 15 is limited by the performance of the machine itself, the data processed per unit time has an upper limit of a certain flow rate. The solid state drive 15 writes the user data 20 and the internal data 21 while simultaneously writing the time period A, in order to maintain the user data 20 access performance at a certain level, and avoid excessive processing of the internal data 21, which affects the user data 20 Access performance. The present invention simultaneously writes the internal data 21 and the user data 20 simultaneously into the period A, increases the writing time T1 of the internal data 21 to the preset extended writing time T2, and reduces the internal time by lengthening the processing time. The write traffic of the data 21. The controller 16 is caused to reduce the internal data 21 processed and written, and spend more time writing to the user data 20 to improve the access performance of the user data 20.

Since the access performance of the user data 20 is based on the unit time as the evaluation standard, the present invention writes the internal data 21 for an extended period of time, reduces the write flow of the internal data 21 units, disperses the internal data 21, and reduces the processing time per unit time. The internal data 21 can avoid the processing time of the user data 20 at the same time, so that the user data 20 processed per unit time can be increased. Comparing the prior art FIG. 5 with the user data 20 access performance curve P of the simultaneous writing period A of FIG. 3 of the present invention, the present invention substantially improves the access performance of the user data 20, and the user data 20 access performance curve P is intense. The undulation phenomenon and the upper and lower shadow lines L are also greatly reduced, indicating that the user data 20 access performance is more stable.

Referring to FIG. 2 again, since the written internal data 21 has higher priority than the written user data 20, when the solid state hard disk 15 finishes writing the internal data 21, only the write of the user data 20 is separately written. When entering the time period B, the controller 16 of the solid state hard disk 15 will fully process the write data to the user data 20. The write traffic of the user data 20 will be greatly increased, although the access performance of the user data 20 can be greatly improved, but The access performance of the user data 20 before and after the time difference is too large to maintain stable performance. In addition, the written user data 20 traffic is greatly increased, and it is also necessary to sequentially process the write flash memory array 18 via the first-in-first-out data pipeline. The speed of processing data by each of the first-in-first-out data pipelines will result in the mutual exclusion of the written user data 20, thereby dragging down the access performance of the user data 20.

In order to maintain stable write performance, the solid state hard disk 15 of the present invention simultaneously processes the extended write time T2 of the internal data 21 and the user data 20 at the simultaneous write period A when the user data 20 and the internal data 21 are simultaneously written. The amount of data written is divided by the amount of data divided by the extended writing time T2, and the write flow rate of the user data 20 at the simultaneous writing period A is calculated. Then, by dividing the amount of write data remaining in the user data 20 by the write flow rate of the simultaneous write period A, the parameter of the delay time T3 is learned. The controller 16 of the solid state hard disk 15 uses the delay time T3 to extend the write time of the user data 20, control the write traffic of the user data 20 of the individual write period B, and reduce the write traffic to approximately equal to the simultaneous write period. A write traffic. Although there is no interference written by the internal data 21 in the separate writing period B, the writing performance of the user data 20 is improved. Comparing the prior art FIG. 5 with the user data 20 access performance curve P of the separate writing period B of FIG. 3 of the present invention, the present invention substantially improves the access performance of the user data 20, and reduces the write traffic of the user data 20, The solid state hard disk 15 is more capable of processing and writing the user data 20, so as to prevent the user data 20 from being mutually crowded, and the upper and lower shadow lines L of the access performance curve P are also greatly shortened, and the user data 20 is more stable in access performance.

As shown in FIG. 4, a solid state hard disk control method for controlling write traffic according to another embodiment of the present invention. The method of controlling the write traffic by the solid state hard disk of this embodiment is the same as that of the previous embodiment. For simplification of description, the same components follow the part number of the previous embodiment. This embodiment differs from the previous embodiment mainly in the implementation of extending the write time T2 and the delay time T3. In the present embodiment, when the write time T2 is extended, the internal data 21 is intermittently written by using the fixed or unfixed interval time m while maintaining the write flow rate of the original internal data 21, so that the internal data 21 is extended in the write time. T2 completes the write to control the reduction of internal data 21 write traffic per unit time. In the embodiment, for the delay time T3, the user data 20 is intermittently written by using the fixed or unfixed interval time n while maintaining the original user data 20 write flow rate, so that the user data 20 is completed at the delay time T3. Write to control the reduction of user data 20 write traffic per unit time. The same processing time can be provided, so that the embodiment can achieve the purpose of stabilizing user data access performance.

As shown in FIG. 5, it is a flowchart of a method for controlling write traffic of a solid state hard disk according to the present invention. The detailed steps of controlling the write traffic by the solid state hard disk of the present invention are as follows: First, in step S1, the write time of the internal data is increased to a preset extended write time to control the reduction of the write traffic of the internal data; in step S2, At the same time, the user data and the internal data are simultaneously written in the writing period; in step S3, it is checked whether the internal data is written. If the internal data is not completed, return to step S2 to continue the simultaneous writing. If the internal data has been written, then to step S4, the user data is written by the user of the simultaneous writing period, and the delay time is learned; In step S5, the delay time is used to control the write traffic of the user data in the separate writing period, and the write traffic of the user data is reduced.

Therefore, the method for controlling the write traffic of the solid-state hard disk of the present invention can increase the write time of the internal data and increase the write flow of the internal data by increasing the write time of the internal data and the user data at the same time. The data is written into the traffic to improve the performance of the user data. And in the simultaneous writing period, learning the writing flow of the user data, forming a parameter of the delay time of the separate writing period, delay writing the user data in the separate writing period, and controlling the writing flow of the user data is reduced. Stabilize the write performance of user data.

The above is only a preferred embodiment for facilitating the description of the present invention, and the scope of the present invention is not limited to the preferred embodiments, and any changes made in accordance with the present invention may be made without departing from the spirit of the present invention. All of them are within the scope of the patent application of the present invention.

Claims (9)

 A method for controlling write traffic by a solid state hard disk, the method comprising: controlling to reduce write traffic of internal data; simultaneously writing user data and internal data during a simultaneous write period; and checking when writing internal data is completed At the same time, the user data of the writing period is written into the traffic, and the delay time is learned; in the separate writing period, the delay time control is used to reduce the writing traffic of the user data.    The method of claim 1, wherein the internal data includes a backup of a logical entity comparison table or a valid data page of a garbage collection data block.    The solid-state hard disk control write flow method according to claim 1, wherein the write time of the internal data is increased to a preset extended write time to reduce the write flow of the internal data.    The method for controlling write traffic by the solid state hard disk according to claim 3, wherein the internal data is intermittently written by using a fixed or unfixed interval, so that the internal data is written at a preset extended write time. In.    The method for controlling write traffic by the solid state hard disk according to claim 3, wherein in the simultaneous writing period, the extended writing time of the internal data and the written data amount of the user data are recorded, and the written data is written. The amount is divided by the extended write time to calculate the write traffic of the user data during the simultaneous write period.    A method for controlling write traffic by a solid state hard disk as described in claim 5, wherein the amount of write data remaining in the user data of the time period is separately divided, and the user data is written in the simultaneous write period. Traffic, learn the delay time.    A method of controlling write traffic by a solid state hard disk as described in claim 6 wherein the delay time is used to extend the write time of the user data.    The method of controlling the write traffic by the solid state hard disk according to claim 6 of the patent application, wherein the user data is intermittently written by using a fixed or unfixed interval, and the user data is written in the delay time.    The method for controlling the write traffic of the solid state hard disk according to the first aspect of the patent application, wherein when the internal data is not completed, the user data and the internal data are continuously written.