KR20040039709A - apparatus and method for high-speed storage - Google Patents

Abstract

PURPOSE: A very high speed storage and a method thereof are provided to offer a high speed memory access while keeping an interface rule between a sub storage and a CPU, and increase an entire service quality and stability without using an expensive server on a server-grade computer offering a service to many users. CONSTITUTION: A memory module(200) stores data by forming more than one module in parallel. A backup HDD(Hard Disk Drive)(300) performs backup of the data stored in the memory module in preparation for power interception and transfer. A controller(100) performs an instruction by interpreting a protocol instruction through an interface with a host, and records a change to the backup HDD if contents of the memory module are changed according to the instruction.

Description

{Apparatus and method for high-speed storage}

The present invention relates to a storage device used in a computer, and more particularly, to a storage device and a method for increasing the speed of a secondary storage device of the computer.

The computer consists of input device, output device, memory device, and arithmetic device. Among them, the memory device is a main memory device that directly controls for operation in the arithmetic device and temporarily stores instructions for execution, and calculated results and various data. There is an auxiliary memory for storing the back.

Therefore, since the main memory device is used for the calculation in the central processing unit, which is an arithmetic unit, the main memory unit focuses on high-speed operation, and the auxiliary memory unit focuses on the capacity for storing various data. As a main memory device, a semiconductor memory device (ROM) or a RAM is mainly used, and as a secondary memory device, a floppy disk, a hard disk, a magnetic drum, a magnetic tape, or the like is used.

Such an auxiliary memory device must be able to freely read / write a large amount of data, and has a non-volatile characteristic that must be able to preserve data even when the power is cut off. .

Due to these characteristics, a hard disk (HDD), which has been widely used as an auxiliary memory device for a long time, uses a magnetic disk as a recording medium, and satisfies the characteristics of the aforementioned auxiliary memory device well.

However, hard disks are developing at a relatively slow speed compared to computer computing units (CPUs), which are rapidly progressing in recent years, and the gap between access processing speeds between internal CPUs and storage devices is increasing.

That is, the aforementioned principle of the hard disk uses a method in which a circular platter is rotated at a high speed, and a head and an arm capable of recording magnetic information move on the platter to record data.

This approach makes it easy to create large amounts of data storage at relatively low cost, but the limitations of keeping up with the speed of electronics, computer motherboards, are due to the fundamental structure of mechanical devices.

Therefore, in order to overcome this limitation by increasing the speed of data access, the platter must be rotated at high speed, and hard disks currently on the market are limited to about 15000 rpm. In addition, even if this speed increases further, the speed gap is expected to increase due to the development of technology of other electronic components (CPU, memory, controller).

On the other hand, a server-class computer serving a large number of users may cause tens or hundreds of services to accumulate in queues or buffers because of a few seconds of service interruption, thereby degrading the quality and stability of the overall service. As a result, the use of a hard disk as an auxiliary storage device has a bigger problem.

Accordingly, in recent years, memory devices capable of easily erasing and writing a large amount of data have been developed due to the continuous development of semiconductor technology, and many attempts have been made to replace the above-described hard disks using the memory devices to be used as auxiliary storage devices. It has been.

A representative example of such attempts is to use flash memory as a secondary memory.

Since the flash memory satisfies all the characteristics of the above-described auxiliary memory device and is also an electronic device, a null memory is mainly used as an auxiliary memory device using a universal serial bus (USB) interface.

However, in spite of the advantage that the data is maintained even when the power supply is interrupted, the flash memory has a disadvantage that it cannot write more than a certain number of times. That is, if you erase or write data for a certain number of times, the memory function will be lost.

In addition, the flash memory is significantly slower than the DRAM used as the main memory, and thus is not suitable for frequent data read / write operations. Therefore, flash memory is currently used as a portable auxiliary memory device which mainly focuses on mobility (replacement of floppy disk or CDROM).

As a way to solve this limitation of read / write times and speed, the increase of DRAM used as main memory can be considered.

In other words, the workstation-class PC does not provide more than three slots of memory (typically RAM) installed in the main board. The reason is that in order to connect four or more modules in parallel, a fan-out is required. This is because it is very difficult to construct a stable circuit because each module affects different modules such as problems and racing problems of control signals.

In addition, except for the module used for the main memory among the three slots, the slot that can be used as the auxiliary storage device is limited to one or two, there is a limitation in implementing a large capacity auxiliary storage device.

For example, in the case of PC2100 or PC2700, which is the standard for DDRRAM memory modules, the theoretical maximum capacity of one module is 4GB, so it is impossible to extend it beyond 12GB.

However, since the capacity is shared with main memory that cannot be used as auxiliary memory, the actual capacity is less than 12GB.

In the case of a server-class computer used as a server, a manufacturer may support a large memory of up to 10GB or more by manufacturing a separate memory board, but such a computer is a high-priced device with hundreds of millions of expensive equipment per unit. Since it costs ten million won, using such expensive equipment just to use a lot of memory is not economical. In addition, even if the main memory is expanded, the auxiliary memory is also correspondingly large, so that the capacity of the main memory is not significant.

In addition, when the main memory RAM is used as an auxiliary memory device, the power of the system must be maintained at all times, and when moving, the mobility must also be reduced with the main body at all times.

Due to such a problem, although the flash memory and the main memory have many advantages, they are not widely used as auxiliary memories.

Accordingly, an object of the present invention is to provide a storage device and a method for providing high-speed memory access while maintaining an existing interface protocol between an auxiliary storage device and a CPU.

Another object of the present invention is to provide a storage device that can increase the quality and stability of the overall service without using an expensive server in a server-class computer serving a large number of users.

It is still another object of the present invention to provide a high-performance server with excellent data availability at a lower cost than conventional auxiliary storage devices.

1 is a block diagram showing an embodiment of an ultra-fast storage device using a memory device according to the present invention

2A and 2B are flowcharts showing the operation of the ultrafast storage device using the memory device according to the present invention.

* Explanation of symbols for main parts of the drawings

110: memory controller 120: interface controller

122: data buffer 130: dirty buffer

140: backup controller 200: memory module

300: backup HDD400: interface connector

Features of the ultra-fast storage device according to the present invention for achieving the above object is a memory module for storing data by combining one or more modules, a backup HDD for backing up the data stored in the memory module, the host and the memory The controller may be configured to decode a corresponding protocol command through an interface with a module to perform a command, and write a controller to the backup HDD when the contents of the memory module change according to the command.

In this case, the controller receives and decodes a corresponding protocol command according to an interface with the host through the interface connector, and then outputs a control signal for executing the command, and the LBA (Linear) as a control signal of the interface controller as an input. A memory controller that performs memory I / O of the memory module by converting a block addressing into a corresponding memory address, and reads the changed contents when the contents of the memory module are changed by a write command from the host. It has a different feature, including a backup controller that writes to a.

The backup controller further includes a dirty buffer for recording a sector number of a corresponding sector of the backup HDD 300 for backing up the changed contents of the memory module.

In this case, it is preferable that the interface controller, the memory controller, and the backup controller are composed of ICs in which all circuits are integrated in one integrated controller.

The memory module may be configured of at least one of SDRAM, DDRRAM, and RDRAM.

It further comprises an interface connector for connecting a connection cable according to the interface with the host, wherein the interface connector is composed of at least one of IEEE1394, SCSI series (Series), ATA series, PCI series and AGP (Acceration Graphic Port) desirable.

The memory module has one or more features in which one or more modules are configured in parallel.

Features of the ultra-fast storage device according to the present invention for achieving the above object is composed of a memory module for storing data, a backup HDD for backing up the data of the memory module, and a controller for controlling the memory module and the backup HDD In the storage method of the ultra-fast storage device, each controller performs its own reset procedure when the power is supplied, the initialization procedure step of sequentially reading the data stored in the backup HDD to write to the memory module, and is transmitted from the host Deciphering the command, and determining whether the command is a read command, a write command, a control command, and if the result of the determination is a read command, reading a few sectors starting from a specific LBA of the memory module and transmitting the read command to the host. And if the determination result is a write command, the data is received from the host. And a write performing step of writing a plurality of sectors starting from a specific LBA of a memory module and writing the recorded data to the backup HDD, and a control performing step of controlling an operation according to a control command if the control result is a control command. To lose.

In this case, the reading step is to decode the command when the read command is transmitted from the host, detect the LBA value and the number of sectors, convert the detected LBA value and the number of sectors into a physical memory address to the memory The module comprises reading the corresponding data desired by the module and transmitting the read data to the host.

The write operation may include decrypting a corresponding command when a write command is transmitted from a host, and storing the data transmitted from the host in a first buffer; and storing the LBA value and sector when the data is stored in the first buffer. Detecting a number, converting the detected LBA value and the number of sectors into a physical memory address, writing the data stored in the first buffer to a corresponding position of the memory module, and storing the LBA value in a second buffer. Recording the data and transmitting a write completion reply to the host; and monitoring the second buffer and reading the corresponding data from the memory module in real time when the LBA value is recorded, and storing the data in a predetermined area of the backup HDD. There is another feature.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

A preferred embodiment of the ultrafast storage device and method using a memory device according to the present invention will be described below with reference to the accompanying drawings.

1 is a block diagram showing an embodiment of an ultrafast storage device using the memory device according to the present invention.

Referring to FIG. 1, one or more modules are formed in parallel to store data, and a backup HDD 300 for backing up data stored in the memory module 200 in preparation for power interruption and movement. And a controller 100 that decodes the corresponding protocol command through an interface with the host to perform the command, and writes the data to the backup HDD when the contents of the memory module 200 change according to the command.

At this time, it further comprises an interface connector 400 for connecting the connection cable according to the interface with the host.

And the controller 100 according to the interface with the host through the interface connector 400, the corresponding protocol commands such as AT Attachment Packet Interface (ATAPI), SCSI (Small Computer System Interface), Serial ATA (SerialATA) The controller receives the decoding and outputs a control signal for performing a command, and converts the LBA into a corresponding memory address by inputting the control signal of the interface controller 120 to the memory module 200. Memory controller 110 that performs memory input / output (I / O), and when the contents of the memory module 200 change due to a write command from the host, the contents of the corresponding sector are read from the memory module 200. The backup controller 140 records the backup HDD 300.

In this case, the backup controller 140 further includes a dirty buffer 130 for recording a sector number of a corresponding sector of the backup HDD 300 for backing up the changed contents of the memory module 200.

Since each of the controllers 110, 120, and 140 must perform high-speed data processing in units of 1 ns in order to comply with the standard of the existing ATAPI-7 or Ultra320 SCSI interface, an independent IC board may be used as a conventional electronic circuit. It is not possible to mount and operate on. Therefore, for such high-speed data processing, it is preferable to configure the interface controller 120, the memory controller 110, and the backup controller 140 as an IC in which all circuits are integrated in one integrated controller.

In addition, the interface connector 400 uses one of IEEE 1394, SCSI series, ATA series, PCI series, and Acceleration Graphic Port (AGP) for high speed data processing.

The LBA is one of the methods commonly used to find a specific sector in the backup HDD 300. The LBA includes a CS (Cylinder Head Sector) method and a LBA (Linear Block Addressing) method.

The CHS method is a method in which a host directly accesses by designating a cylinder, a head, and a sector value of a backup HDD 300. The LBA method assigns a serial number to each sector, as if there are consecutive sectors. By specifying only the LBA value in the host, this value is converted to the actual CHS value and accessed.

At this time, the CHS value has a unique parameter for each hard disk, so access is cumbersome. In the present invention, the LBA method is used as a preferred embodiment.

The memory module 200 is composed of SDRAM, DDRRAM, RDRAM, and the like, and is used in the form of most standardized modules except for a server-class computer using its own RAM board. In the present invention, the memory module 200 is used as the most preferred DDRRAM on the market.

In this case, the DDRRAM is provided in the form of a module of 184 pins according to the specifications of PC2100 and PC2700, and provides data transfer speeds of 2.1 GB / sec and 2.7 GB / sec, respectively, with a bandwidth of 64 bits.

In addition, the memory controller 110 internally reads and writes an arbitrary area of the memory module 200 in which a plurality of modules are mounted in parallel.

In addition, when the contents are changed in any part of the memory module 200, the backup controller 140 reflects the changes to the backup HDD 300 as a post-operation to prepare for power cut.

The operation of the ultrafast storage device using the memory device according to the present invention configured as described above will be described in detail with reference to the accompanying drawings.

Generally, the core of communication protocol, whether ATAPI or SCSI, can be classified into read command, write command, and control command.

However, in the existing HDD, a controller for processing such a command is implemented in the HDD. However, in the present invention, the interface controller 120 may be installed separately in place of this role to handle the interface with the host.

2A and 2B are flowcharts illustrating the operation of the ultrafast storage device using the memory device according to the present invention.

As shown in FIGS. 2A and 2B, the operation of the ultrafast storage device is largely composed of an initialization procedure step S100, a read command step S200, a write command step S300, and a control command step S400.

When power is initially supplied to the initialization procedure step S100 (S110), each of the memory controller 110, the backup controller 140, and the interface controller 120 performs its own reset procedure (S120).

Subsequently, the data is sequentially read from the first LBA to the last LBA of the data stored in the backup HDD 300 and is then controlled by the memory controller 110 and recorded in the memory module 200 (S130).

After that, the data requested by the host is always read through the memory module 200.

When the initialization procedure is completed as described above, it is determined whether the command transmitted from the host through the interface controller 120 is a read command, a write command, or a control command (S200).

As a result of the determination, in the case of a read command, a read command step (S300) of reading several sectors from a specific LBA is transmitted to the host, and in the case of a write command, data is received from the host and written to several sectors from a specific LBA And a write command step (S400) for recording the recorded data on the backup HDD 300, and in the case of a control command, a control command step (S500) for controlling the reset and mode conversion of the backup HDD 300, and the like. Perform

The steps of the read command, write command, and control command will be described in more detail as follows.

In the read command step (S300), first, when a read command is transmitted from the host, the interface controller 120 decodes the corresponding command (S310), and then detects the LBA value and the number of sectors and transmits it to the memory controller 110 ( S320).

Then, the memory controller 110 reads the transmitted LBA value and the number of sectors, converts the LBA value into a physical memory address, and reads desired data from the memory module 200 (S330).

The read data is transmitted to the host through the interface controller 120 (S340).

In the write command step (S400), first, when a write command is transmitted from the host, the interface controller 120 decodes the corresponding command (S410), and then stores the data transmitted from the host in the data buffer 121 (S420). .

When all data is stored in the data buffer 121 after the data transfer is completed, the interface controller 120 transmits the LBA value and the number of sectors to the memory controller 110 (S430).

Next, the memory controller 110 reads the transmitted LBA value and the number of sectors, converts the LBA value into a physical memory address, and writes the data stored in the data buffer 121 at a corresponding position of the memory module 200 (S440). .

When all data of the data buffer 121 is written to the memory module 200, the interface controller 120 writes the corresponding LBA value to the dirty buffer 130 (S450).

When the recording is completed, the interface controller 120 sends a recording completion reply to the host so that the host can perform the next operation (S460).

The backup controller 140 monitors the dirty buffer 130 and reads the corresponding data from the memory module 200 and stores the data in the predetermined area of the backup HDD 300 when the LBA value is recorded (S470).

The backup controller 140 monitors the portion where the contents of the memory module 200 are converted and reflects the necessary portion to the backup HDD 300 in real time in order to maintain data even when the power is cut off.

At this time, the memory controller 110 and the backup controller 140 is a task that is performed independently, when the data A, B, and C are written in the host in order, A is stored in the memory module 200 and A is backed up in the backup HDD 300. , May be executed in the order of B storage in the memory module 200, B backup in the backup HDD 300, C storage in the memory module 200, and C backup in the backup HDD 300, but successively in the memory module 200. A, B, C storage, the backup HDD 300 may be executed in the order of A, B, C backup.

As described above, since the independent controller processes each of the data stored in the memory module 200 and the backup HDD 300 during data storage, the backup is always performed sequentially in the memory module 200 and the backup HDD 300. There is no support.

In this case, since the backup speed of the backup HDD 300 is slower than that stored in the memory module 200, when a large amount of data is momentarily stored, only the LBAs are stored in the memory and the dirty buffer 121 once. The backup of the data may be performed later after being stored in the memory module 200.

When the data is completed to be stored in the backup HDD 300, the LBA stored in the dirty buffer 130 is deleted or overwritten to the next recorded LBA.

Finally, the control command step (S500), first, when a write command is transmitted from the host, the interface controller 120 decrypts the corresponding command (S510).

According to the decrypted control command, an appropriate operation such as resetting of the backup HDD 300 and mode switching is performed (S520). At this time, if necessary, the command is transmitted to the memory controller 110 or the backup controller 140 to perform a control command to the memory module 200 and the backup HDD 300.

Thereafter, if the next job is transmitted through the host, the process is repeated (S600).

The ultrafast storage device and method according to the present invention as described above has the following effects.

First, it maintains the interface protocol between the existing hard disk and the host, and can provide high-speed I / O by expanding only the memory device without expansion or replacement in the existing equipment.

Second, data availability is higher than that of a conventional hard disk, and a high performance server can be achieved at a relatively low cost.

Third, by replacing a hard disk that is a mechanical device with a plurality of RAM modules and a backup HDD that are electronic devices, a processing speed of 20 times or more can be increased.

Fourth, by operating the backup HDD to make up for the shortcomings of the memory module, it is possible to solve the difficulty of maintaining the power at all times and to prevent data loss in the event of a power failure or sudden failure. Can be implemented.

Fifth, since it is connected to the main body and the interface cable can be used apart from the main body at the time of movement, there is an excellent mobility effect.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (13)

A memory module in which one or more modules are combined to store data; And a controller configured to decode a corresponding protocol command through an interface between a host and the memory module to perform a command, and to read / write the contents of the memory module according to the command. The method of claim 1, wherein the controller An interface controller for receiving and decoding a corresponding protocol command according to an interface with a host through the interface connector and outputting a control signal for executing the command; And a memory controller configured to convert LBA (Linear Block Addressing) into a corresponding memory address by inputting the control signal of the interface controller to perform memory I / O of the memory module. . The method of claim 2, And the interface controller and the memory controller are configured as ICs in which all circuits are physically integrated in one integrated controller. The method of claim 1, And a backup HDD for backing up data stored in the memory module. The method of claim 4, wherein And a backup controller which reads the changed contents and writes them to the backup HDD when the contents of the memory module change due to a write command from the host. The method of claim 5, wherein The backup controller further includes a dirty buffer for recording a sector number of a corresponding sector of the backup HDD for backing up the changed contents of the memory module. The method of claim 1, The memory module of claim 1, wherein the memory module comprises at least one of SDRAM, DDRRAM, and RDRAM. The method of claim 1, And an interface connector for connecting a connection cable according to the interface with the host. The method of claim 8, The interface connector is characterized in that at least one of the IEEE1394, SCSI series (Series), ATA series, PCI series and AGP (Acceration Graphic Port) characterized in that the configuration. The method of claim 1, The memory module of claim 1, wherein at least one module is configured in parallel. In the storage method of the ultra-fast storage device comprising a memory module for storing data, a backup HDD for backing up the data of the memory module, and a controller for controlling the memory module and the backup HDD, An initialization procedure step in which each controller performs its own reset procedure when the power is supplied and sequentially reads data stored in the backup HDD and writes the data to the memory module; Decoding a command transmitted from a host, and determining whether the command is a read command, a write command, or a control command; A read performing step of reading a few sectors starting from a specific LBA of the memory module and transmitting the read command to the host if the read command is performed; If it is determined that the command is a write command, write data is received from a host and written to several sectors starting from a specific LBA of the memory module, and the recorded data is written to the backup HDD; And a control execution step of controlling an operation according to the control command if the control command is a result of the determination. 12. The method of claim 11, wherein performing a read When a read command is sent from the host, the command is decoded and the LBA value and the number of sectors are detected. Converting the detected LBA value and the number of sectors into a physical memory address and reading desired data from the memory module; And transmitting the read data to a host. 12. The method of claim 11, wherein the writing step is performed. Decrypting the command when the write command is transmitted from the host, and storing the data transmitted from the host in a first buffer; Detecting the LBA value and the number of sectors when all data is stored in the first buffer; Converting the detected LBA value and the number of sectors into a physical memory address and writing data stored in the first buffer to a corresponding position of the memory module; Writing the LBA value to a second buffer and sending a write complete reply to a host; And monitoring the second buffer and reading the corresponding data from the memory module in real time when the LBA value is recorded, and storing the data in a predetermined area of the backup HDD.