WO2021082109A1

WO2021082109A1 - Hybrid mapping table on static random access memory

Info

Publication number: WO2021082109A1
Application number: PCT/CN2019/119687
Authority: WO
Inventors: 张盛豪; 魏智汎; 王展南; 谢享奇
Original assignee: 江苏华存电子科技有限公司
Priority date: 2019-10-31
Filing date: 2019-11-20
Publication date: 2021-05-06
Also published as: CN110806987A

Abstract

A hybrid mapping table on a static random access memory. A mapping table on a static random access memory is combined with a mapping table mapped to a fast buffer storage area. The usage of space by the static random access memory can be saved, and the utilization rate of the static random access memory can be effectively improved. According to the size of the fast buffer storage area, the space usage of n static random access memories can also be reduced.

Description

A hybrid mapping table on static random access memory

Technical field

The invention relates to the technical field of storage systems, in particular to a hybrid mapping table on a static random access memory.

Background technique

Flash memory (flash memory, sometimes referred to as flash RAM) is a non-volatile memory with continuous power supply, which can be deleted and reorganized in storage units called blocks. Flash memory is a variant of electrically erasable programmable read-only memory (EEPROM). The difference between EEPROM and flash memory is that it deletes and rewrites at the byte level, so that the update speed of EEPROM is slower than flash memory. Flash memory is usually used to store control codes, such as the basic input output system (BIOS) in a personal computer. When the input/output system needs to be changed (rewritten), the flash memory can be written in blocks (rather than bytes), so that the flash memory can be updated more easily. But on the other hand, flash memory is not as useful as random access memory (RAM), because random access memory can set addresses at the byte (rather than block) level.

The application of flash memory storage is quite extensive, but the space of static random access memory is also reflected in the cost price. Therefore, the efficient use of static random access memory is a major issue.

In a flash storage system, how to mark whether user data has a flash translation layer (FTL, Flash Translation Layer) fast buffer storage area (SLC area). Each manufacturer on the market has its own unique method. The common method is to use Byte to record the user data currently in the fast buffer storage area in a space of the static random access memory. When the flash conversion layer needs to search for user data, it needs to first search the static random access memory marked with the fast buffer storage area to find whether the currently needed data exists in the fast buffer storage area. If the currently needed data is not in the fast buffer storage area, look up the mapping table to look up the needed data.

Summary of the invention

The object of the present invention is to provide a hybrid mapping table on a static random access memory to solve the above-mentioned problems in the background art.

To achieve the above objective, the present invention provides the following technical solution: a hybrid mapping table on a static random access memory, including the following steps:

Step 1: Query information;

Step 2: Determine the highest position, if yes, skip to step 3, otherwise skip to step 4;

Step 3: Look up the physical block address of the fast buffer storage area;

Step 4: Reload the image table;

Step 5: Look up the physical block address of the data from the mapping table.

Preferably, the mapping table is any mapping table, which can be mixed with the erase block count table and the effective unit count table.

Preferably, the fast buffer storage area has 200 SLCs, each SLC has 256 flash memory pages, each page has 16K space, and every 4K is a space unit.

Compared with the prior art, the present invention has the beneficial effect that: the present invention combines the mapping table on the static random access memory with the mapping table mapped to the fast buffer storage area. That is, the space usage of the static random access memory can be saved, so as to effectively increase the utilization rate of the static random access memory. According to the size of the fast buffer storage area, the space usage of n static random access memories can also be reduced.

Description of the drawings

Figure 1 is a flow chart of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

Referring to Fig. 1, the present invention provides a technical solution: a hybrid mapping table on a static random access memory, including the following steps:

Step 1: Query information;

Step 3: Look up the physical block address of the fast buffer storage area;

Step 4: Reload the image table;

Step 5: Look up the physical block address of the data from the mapping table.

Among them, the map table is any map table, which can be mixed with the erase block count table and the effective unit count table.

The fast buffer storage area has 200 SLCs, each SLC has 256 flash pages, and each page has 16K of space. Every 4K is a space unit. It can save 200*256*4 of 204800 static random access memory space.

In the present invention, the state of the user data in the fast buffer storage area is marked at the highest bit of the mapping table. By marking the highest bit of the mapping table, it is noted whether the user data to be searched exists in the fast buffer storage area. Mark with a bit. The highest bit is 1, it means that the user data is stored in the fast buffer storage area. The highest bit is 0, it means that the user data does not exist in the fast buffer storage area. At this time, the mapping table needs to be reloaded to look up the physical block address.

In summary, the present invention combines the mapping table on the static random access memory with the mapping table mapped to the fast buffer storage area. That is, the space usage of the static random access memory can be saved, so as to effectively increase the utilization rate of the static random access memory. According to the size of the fast buffer storage area, the space usage of n static random access memories can also be reduced.

Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, and substitutions can be made to these embodiments without departing from the principle and spirit of the present invention. And variations, the scope of the present invention is defined by the appended claims and their equivalents.

Claims

A hybrid mapping table on a static random access memory, which is characterized in that it includes the following steps:

Step 1: Query information;

Step 2: Determine the highest position, if yes, skip to step 3, otherwise skip to step 4;

Step 3: Look up the physical block address of the fast buffer storage area;

Step 4: Reload the image table;

Step 5: Look up the physical block address of the data from the mapping table.
A hybrid mapping table on a static random access memory according to claim 1, characterized in that: the mapping table is any mapping table, which can be combined with the erase block count table and the effective unit count Table mix.
A hybrid mapping table on a static random access memory according to claim 1, wherein the fast buffer storage area has 200 SLCs, each SLC has 256 flash memory pages, and each page has 200 SLCs. 16K space, every 4K is a space unit.