JP2009104410A - Data recording device, internal control method thereof, and data recording system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To set a timeout value corresponding to AV data and the other data, relating to a data recording device which writes/reads the AV data as well as other data on/out of a plurality of HDDs based on the command from an upper-class control device. <P>SOLUTION: The data recording device includes a control part 11-2 which performs: a process for setting a limit on the time duration corresponding to the number of sectors required through the command received from a control device 11-1 of a higher order; a process for issuing a command corresponding to the command received from the control device 11-1, with a set limit time specified, to HDD controllers 14-1 to 14-6; and a process for responding to the control device 11-1 based on the result of writing/reading only with such HDD in which the process of writing/reading has been completed within the limit time among HDDs 15-1 to 15-6. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention provides data for writing / reading AV data (video data and audio data) and writing / reading other data to / from a plurality of hard disk drives based on commands from a host control device. The present invention relates to a recording apparatus.

  Devices (RAID devices) that record AV data on a plurality of hard disk drives using RAID (Redundant Arrays of Inexpensive Disks) technology are widely used as data recording devices for business use and professional use. Such a RAID apparatus normally performs writing / reading of AV data based on a command transmitted from a host control apparatus.

  Hard disk drives have restrictions on access time (time from when a data write / read command is received until data is actually written / read) because of seeking the head and waiting for rotation of the target sector. . Therefore, in a system that reproduces video data seamlessly, it is necessary to set a time limit on write / read processing of the RAID device. Therefore, a RAID device has conventionally been provided with a timeout function. This timeout function will be described with reference to FIGS.

  FIG. 1 shows an example of a timeout value (time limit) for the read processing of the RAID device. As shown in FIG. 1A, when video data D1, D2,... Each having a constant data size is reproduced without a break at a constant time interval Tp, the next video is reproduced before the video data D1 finishes playing. The data D2 needs to be transferred from the RAID device to the host control device.

  FIG. 1B shows the timing at which a transfer request (read command) of the video data D2 is transmitted from the host control device to the RAID device. The time from the timing until the reproduction of the video data D1 is completed is Tw.

  As shown in FIG. 1C, if the maximum time required to transfer the video data D2 from the RAID device to the host control device is Tt, the video data D2 is transferred to the host control device within the time Tw. In order to transfer, the RAID device must finish reading the video data D2 within the time Ti = Tw−Tt. Therefore, this time Ti is set as a timeout value for the reading process of the RAID device.

  FIG. 2 shows an example of internal control of the RAID device by the timeout function. In the RAID device, video data and an error correction code generated from the video data are distributed and recorded in a plurality of hard disk drives HDD1 to HDD6. Therefore, in the RAID device, a read command received from a host control device is used. Correspondingly, a read command is issued to each HDD1 to HDD6.

  Then, after issuing this read command, at the timing when the timeout value Ti (Ti shown in FIG. 1) has elapsed, data from only the HDDs HDD4 to HDD4 and HDD6 that have completed the read processing among the HDD1 to HDD6 is used. The original video data is restored, and the restored video data is transferred to the host control device.

  In the conventional RAID device, the timeout value in this timeout function is set to a fixed value in advance, or set to a value designated on the upper control device side.

  In addition, a technique for setting a timeout value in accordance with a bit rate of data to be read has been conventionally proposed in a RAID apparatus that records AV data (Patent Document 1).

JP 2007-199934 A

  By the way, the RAID device not only writes / reads AV data, but also other data (for example, log information of the operation of the RAID device, management information by the file system of data recorded in the RAID device, etc.) When trying to use it for writing / reading data, the time-out function of the conventional RAID device causes the following problems (a) to (c).

  (A) Since the data size differs greatly between AV data and log information or file management information, when the timeout value is set to a fixed value, if it is set to one of the values, the value is not appropriate for the other. (For example, if it is set to a value according to AV data as in the prior art, it becomes an unnecessarily long value for writing / reading log information and file management information.)

  (B) Unlike AV data, log information and file management information are information that does not require real-time properties, and application software for writing / reading such information does not have the concept of a timeout value. When the higher-level control device transmits writing / reading of log information or file management information by such application software, the higher-level control device cannot specify a timeout value.

  (C) Since the concept of bit rate does not exist in log information and file management information, it is not possible to set a timeout value according to log information or file management information even using the technique described in Patent Document 1 above. Can not.

  In view of the above points, the present invention provides data recording for writing / reading AV data and writing / reading other data to / from a plurality of hard disk drives based on commands from a host control device. It is an object of the present invention to enable a device to set timeout values corresponding to AV data and other data.

In order to solve this problem, the present invention is based on a write / read command received from a host control device, and writes / reads video data and audio data to / from a plurality of hard disk drives and other data. In a data recording apparatus that performs writing / reading of
A time limit setting process for determining the number of sectors requested by the command received from the control device, and setting a time limit of a length according to the number of sectors;
A command issuing process for specifying a time limit set in the time limit setting process and issuing a command corresponding to a command received from the control device to a hard disk drive controller that controls the plurality of hard disk drives;
Of the plurality of hard disk drives, a response is returned to the control device based on the result of writing / reading only for the hard disk drive that has completed the writing / reading process within the time limit after issuing the command in the command issuing process. And a control unit for performing a reply process.

Further, the present invention performs writing / reading of video data and audio data and writing / reading of other data to / from a plurality of hard disk drives based on a write / read command received from a host controller. In the internal control method of the data recording device to be performed,
A first step of determining the number of sectors required by the command received from the control device, and setting a time limit of a length according to the number of sectors;
A second step of issuing the command corresponding to the command received from the control device and issuing the command corresponding to the command received from the control device to the hard disk drive controller that controls the plurality of hard disk drives by designating the time limit set in the first step When,
Of the plurality of hard disk drives, after the command is issued in the second step, a response is returned to the control device based on the result of the writing / reading of only the hard disk drive that has completed the writing / reading process within the time limit. And performing a third step.

  In this data recording device and the internal control method of the data recording device, when a write / read command is received from a host control device, the number of sectors required by the command is determined, and the length is limited according to the number of sectors. Time (timeout value) is set. Then, by specifying the set time limit, a command corresponding to the command received from the host control device is issued to the hard disk drive controller, and then writing / reading within the time limit among a plurality of hard disk drives. A reply is made to the control unit based on the result of writing / reading of only the hard disk drive that has completed the above processing.

  As described above, the timeout value is variably set according to the number of requested sectors of the write / read command received from the host control device. As a result, the host controller side only needs to make the requested sector number of the AV data write / read command different from the requested sector number of the other data write / read commands. It becomes possible to set timeout values according to AV data and other data.

Next, the present invention provides a data recording apparatus for writing / reading video data and audio data to / from a plurality of hard disk drives and writing / reading other data.
In a data recording system including an upper control device that transmits a data write / read command to the data recording device,
The data recording device comprises:
A time limit setting process for determining the number of sectors requested by the command received from the control device, and setting a time limit of a length according to the number of sectors;
A command issuing process for specifying a time limit set in the time limit setting process and issuing a command corresponding to the command received in the command receiving process to a hard disk drive controller that controls the plurality of hard disk drives;
Of the plurality of hard disk drives, a response is returned to the control device based on the result of writing / reading only for the hard disk drive that has completed the writing / reading process within the time limit after issuing the command in the command issuing process. And a control unit for performing a reply process.

  This data recording system includes the above-described data recording apparatus according to the present invention and a higher-level control apparatus, and the upper-level control apparatus side requests the number of sectors for writing / reading commands for video data and audio data. The data recording apparatus can set a timeout value corresponding to AV data and other data only by making the number of sectors required for a write / read command of other data different from that.

  According to the present invention, in a data recording apparatus that writes / reads AV data to / from a plurality of hard disk drives and writes / reads other data to / from a plurality of hard disk drives based on a command from a host controller. There is an effect that timeout values can be set according to data and other data.

  Embodiments of the present invention will be specifically described below with reference to the drawings. In the following, an example in which the present invention is applied to a digital cinema screening system will be described. First, an outline of the digital cinema screening system will be described.

  FIG. 3 is an overall configuration diagram of a digital cinema screening system to which the present invention is applied. This digital cinema screening system includes a data recording device 1 using a RAID technology, a digital cinema server 2, a projector (projection display device) 3, and a personal computer 4.

  The data recording device 1, the digital cinema server 2, and the projector 3 are housed in the same casing. The digital cinema server 2 and the personal computer 4 are connected by a high-speed network 5 such as 1000BASE-T.

  This digital cinema screening system records AV data of a movie to be screened (video data is compressed by an image compression method such as JPEG2000) from a personal computer 4 to a data recording device 1 via a digital cinema server 2. The AV data reproduced from the data recording device 1 is sent from the digital cinema server 2 to the projector 3 and projected onto the screen.

  In the personal computer 4, on the GUI screen, recording of AV data, movie screening, data other than AV data (log information of operation of the data recording device 1, file system relating to AV data in the data recording device 1) And a program for managing movie subtitle data). From the personal computer 4, AV data write / read requests, log information, file system information, and subtitle data write / read requests are sent to the digital cinema server 2 via the high-speed network 5 based on operations on the GUI screen. Send.

  FIG. 4 is a diagram showing main circuits provided in the digital cinema server 2. In the digital cinema server 2, a CPU 11 and a decoder 20 for decompressing compressed AV data are provided. The CPU 11 is connected to the high-speed network 5 shown in FIG. 3, and is connected to the data recording apparatus 1 shown in FIG. The decoder 20 is connected to the data recording device 1 and to the projector 3 in FIG.

The CPU 11 stores the following three programs (a) to (c).
(A) “Internal control application” which is a program for performing internal control of the data recording apparatus 1
(B) “Digital cinema application” which is a program for transmitting AV data write / read commands to the “internal control application” in accordance with AV data write / read requests from the personal computer 4
(C) A program that transmits log information, file system information, and subtitle data write / read commands to the “internal control application” in accordance with log information, file system information, and subtitle data write / read requests from the personal computer 4. A management application

  Note that the number of sectors of the hard disk requested by the command transmitted by the “management application” is less than 128 sectors per command.

On the other hand, the number of sectors per command requested by a command transmitted by the “digital cinema application” is much larger than that of log data, file system information, and caption data in AV data. In order to guarantee a high data rate, the number of sectors is set larger than that of the “management application” as described below.
-Video data read command: 24000 sectors-Video data write command: 2048 sectors-Audio data write / read commands: 128 sectors or more and less than 2048 sectors

As described above, any of the following methods can be employed as a method for increasing the number of sectors requested for the “digital cinema application” command than the number of sectors requested for the “management application” command.
Data in the data recording device 1 (AV data and data other than AV data) is managed by a general-purpose file system on a general-purpose OS, but the general-purpose file system requires a small number of sectors for writing / reading commands from applications Since the command is divided into a large number of commands, a device driver that bypasses command division by the general-purpose file system is prepared for commands from the “digital cinema application”.
-Instead of a general-purpose file system, build a unique file system that devise the arrangement of data on the hard disk so as to guarantee a high data rate for AV data.

  The CPU 11 functions as a higher-level control device (device that transmits a data write / read command to the data recording device 1) by executing the “digital cinema application” and the “management application”. In addition, it also has a function of performing internal control of the recording apparatus 1 by executing an “internal control application”.

  In the following, in order to make the explanation easy to understand, a part of the CPU 11 that functions as a higher-level control device is referred to as a higher-level control unit 11-1, and a function part that performs internal control of the data recording device 1 is referred to as an internal control unit 11- The CPU 11 is divided into two parts according to functions, as in the description.

  FIG. 5 is a diagram showing the configuration of the data recording apparatus 1 together with the upper control unit 11-1, the internal control unit 11-2, and the decoder 20. Here, the internal control unit 11-2 is shown as a part of the data recording apparatus 1 because of its function. In addition, the flow of data (AV data, log information, file system information, and caption data) is indicated by double arrows, and commands and responses sent and received by the upper control unit 11-1 and the internal control unit 11-2 are shown. The flow is indicated by a single line arrow.

  The data recording apparatus 1 includes an ECC / DMA unit 12 composed of an FPGA, a cache memory 13, and an HDD controller (for example, SAS controller) 14 (14-1 to 14-7) for controlling a total of seven HDDs. Is provided. Out of a total of seven HDDs 15 (15-1 to 15-7) connected to the HDD controller 14, four HDDs 15-1 to 15-4 are for data, and two HDDs 15-5 to 15-6 are errors. For correction, the remaining one HDD 15-7 is for spare.

  At the time of recording, the ECC / DMA unit 12 generates an error correction code from the data sent from the upper control unit 11-1 in the digital cinema server 2, and uses the cache memory 13 for the data to which the error correction code is added. Striped and supplied to the HDDs 15-1 to 15-6 via the HDD controllers 14-1 to 14-6.

  During reproduction, the ECC / DMA unit 12 uses the cache memory 13 to destrip data supplied from the HDDs 15-1 to 15-6 via the HDD controllers 14-1 to 14-6, and the destriped data. Correct the error and restore the original data.

  When reproducing the video data, the video data restored by the ECC / DMA unit 12 is sent to the decoder 20. Then, the baseband video data expanded by the decoder 20 is sent to the projector 3 in FIG. 3 and projected from the projector 3 onto the screen.

  At the time of reproduction of audio data, the audio data restored by the ECC / DMA unit 12 is sent from an audio output terminal (not shown) provided in a housing housing the data recording device 1, the digital cinema server 2, and the projector 3. Output to the outside.

  At the time of reproduction of log information and file system information, the log information and file system information restored by the ECC / DMA unit 12 is sent to the upper control unit 11-1, and the upper control unit 11-1 performs personal computer 4 in FIG. And displayed on the GUI screen on the display of the personal computer 4.

  When reproducing subtitle data, the subtitle data restored by the ECC / DMA unit 12 is sent to a mixing circuit (not shown) provided in the digital cinema server 2 and decompressed by the decoder 20. Synthesized with data.

  The internal control unit 11-2 executes the “internal control application” described above, and controls the ECC / DMA unit 12 and the HDD controller 14. FIG. 6 is a flowchart showing a timeout value setting process which is a part of the process by the “internal control application”.

  This process starts when a write / read command is received from the upper control unit 11-1, and first, it is determined whether the number of sectors requested by the command is 24,000 sectors or more (step S1).

  If yes, the timeout value for processing of the data recording device 1 is set to 650 msec (step S2). Then, the set timeout value (here, 650 msec) is designated, and a command corresponding to the command received from the upper control unit 11-1 is issued to the ECC / DMA unit 12 and the HDD controllers 14-1 to 14-6. (Step S3). Then, the timeout value setting process ends.

  If no in step S1, it is determined whether the number of sectors requested for the command from the upper control unit 11-1 is 2048 sectors or more (step S4).

  If yes, the time-out value for processing of the data recording device 1 is set to 150 msec (step S5). Then, by proceeding to the above-described step S3, the set timeout value (here, 150 msec) is designated, and the command corresponding to the command received from the upper control unit 11-1 is sent to the ECC / DMA unit 12 and the HDD controller 14. -1 to 14-6. Then, the timeout value setting process ends.

  If no in step S4, it is determined whether the number of sectors requested for the command from the upper control unit 11-1 is 128 sectors or more (step S6).

  If yes, the time-out value for processing of the data recording device 1 is set to 130 msec (step S7). Then, by proceeding to the above-described step S3, the set timeout value (here, 130 msec) is designated, and a command corresponding to the command received from the upper control unit 11-1 is sent to the ECC / DMA unit 12 and the HDD controller 14. -1 to 14-6. Then, the timeout value setting process ends.

  If no in step S6, the processing time-out value of the data recording device 1 is set to 80 msec (step S8). Then, by proceeding to the above-described step S3, the set timeout value (80 msec in this case) is designated, and the command corresponding to the command received from the upper control unit 11-1 is sent to the ECC / DMA unit 12 and the HDD controller 14. -1 to 14-6. Then, the timeout value setting process ends.

  As described above, among the commands transmitted from the upper control unit 11-1, the requested sector number of the video data read command is 24000 sectors, the requested sector number of the video data write command is 2048 sectors, and the audio data The number of sectors required for data write / read commands is 128 or more and less than 2048 sectors, and the number of sectors requested for write / read commands for other data (log information, file system information, and caption data) is less than 128 sectors. .

  Accordingly, when a video data read command is transmitted from the host control unit 11-1, the timeout value is set to 650 msec by the timeout value setting process of FIG. 6 (steps S1 to S2), and this timeout value 650 msec is set. Then, a video data read command is issued to the ECC / DMA unit 12 and the HDD controllers 14-1 to 14-6 (step S3).

  As described with reference to FIG. 1, this value of 650 msec is a real-time property in which a movie is played by playing back video data of a constant data size (here, 24,000 sectors) in a constant time interval unit without interruption. This is a value determined from the viewpoint of

  When a video data write command is transmitted from the host control unit 11-1, the timeout value is set to 150 msec by the timeout value setting process in FIG. 6 (steps S4 to S5), and this timeout value 150 msec is set. Then, a video data write command is issued to the ECC / DMA unit 12 and the HDD controllers 14-1 to 14-6 (step S3).

  When an audio data write / read command is transmitted from the upper control unit 11-1, the timeout value is set to 130 msec by the timeout value setting process of FIG. 6 (steps S6 to S7). By designating 130 msec, audio data write / read commands are issued to the ECC / DMA unit 12 and the HDD controllers 14-1 to 14-6 (step S3).

  The values of 150 msec and 130 msec are also values determined from the standpoint of real-time properties in which video data recording and audio data recording / playback are performed seamlessly.

  Further, when a log information, file system information, or subtitle data write / read command is transmitted from the upper control unit 11-1, the timeout value is set to 80 msec by the timeout value setting process of FIG. 6 (step S8). ) Specifying this timeout value of 80 msec, a log information, file system information, and subtitle data write / read command is issued to the ECC / DMA unit 12 and the HDD controllers 14-1 to 14-6 (step S3). become.

  Log information and file system information itself are information that does not require real-time performance for recording and reproduction, and there is no concept of a timeout value in application software that writes / reads such information. However, since these pieces of information are recorded in the same HDDs 15-1 to 15-6 as the AV data, the AV data cannot be recorded / reproduced while the information is recorded / reproduced. Therefore, if it takes a long time to record / reproduce such information, it may cause trouble in seamless recording / reproduction of video data and audio data. Therefore, a timeout value of 80 msec is set for these pieces of information.

  After the timeout value setting process of FIG. 6 is performed, the internal control unit 11-2 only performs the writing / reading process within the timeout value specified by the timeout value setting process among the HDDs 15-1 to 15-6. Based on the result of writing / reading, a response is sent to the host controller 11-1.

  Specifically, for example, when a video data read command is transmitted from the host control unit 11-1, a part of the HDDs 15-1 to 15-6 finishes the read process within 650 msec. If not, the internal control unit 11-2 controls the ECC / DMA unit 12 as described with reference to FIG. 2, and uses only data from the HDD that has completed the read processing within 650 msec. The data is restored and the read result is returned to the upper control unit 11-1. In this case, the ECC / DMA unit 12 restores the original video data by performing destriping and error correction using only data from the HDD that has been read out within 650 msec, but the frame cannot be restored even by error correction. When there is a section, the video data of the restored frame is transferred to the decoder 20 without disturbing the time axis of the reproduction data.

  As described above, in this digital cinema screening system, the data recording device 1 (the internal control unit 11-2 that performs internal control thereof) receives the writing / recording received from the digital cinema server 2 (the upper control unit 11-1). By variably setting the timeout value according to the number of sectors requested for the read command, it is possible to set a timeout value corresponding to AV data and other data (log information, file system information, subtitle data). Yes.

  As a result, the same data recording device 1 is used for recording AV data and recording log information, file system information, etc., while reproducing the AV data seamlessly to display a movie, It is possible to record without.

  In the above embodiment, one CPU 11 in the digital cinema server 2 has both a function as a higher-level control device of the data recording device 1 and a function of performing internal control of the data recording device 1. Yes. However, as another example, the CPU 11 in the digital cinema server 2 has only a function as a higher-level control device of the data recording device 1 (only “digital cinema application” and “management application” are executed). A dedicated CPU that performs internal control of the data recording apparatus 1 (executes an “internal control application”) may be provided inside the data recording apparatus 1.

  In the above embodiment, the present invention is applied to a digital cinema screening system. However, the present invention is applied to any data recording device that performs AV data writing / reading and other data writing / reading with respect to a plurality of HDDs based on commands from a host control device. be able to.

It is a figure which illustrates the timeout value of the read-out process of a RAID apparatus. It is a figure which illustrates the internal control of the RAID apparatus by a timeout function. 1 is an overall configuration diagram of a digital cinema screening system to which the present invention is applied. It is a figure which shows the circuit provided in the digital cinema server of FIG. It is a figure which shows the structure of the data recording device of FIG. It is a flowchart which shows the timeout value setting process which the internal control part of FIG. 5 performs.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Data recording device, 2 Digital cinema server, 3 Projector, 4 Personal computer, 5 High speed network, 11 CPU, 11-1 High-order control part, 11-2 Internal control part, 12 ECC / DMA part, 13 Cache memory, 14- 1-14-7 HDD controller, 15-1-15-7 HDD, 20 decoder

Claims (6)

In a data recording device for writing / reading video data and audio data and writing / reading other data to / from a plurality of hard disk drives based on a write / read command received from a host control device ,
A time limit setting process for determining the number of sectors requested by the command received from the control device, and setting a time limit of a length according to the number of sectors;
A command issuing process for specifying a time limit set in the time limit setting process and issuing a command corresponding to a command received from the control device to a hard disk drive controller that controls the plurality of hard disk drives;
Of the plurality of hard disk drives, a response is returned to the control device based on the result of writing / reading only for the hard disk drive that has completed the writing / reading process within the time limit after issuing the command in the command issuing process. A data recording apparatus comprising a control unit for performing a response process. The data recording apparatus according to claim 1, wherein
The control device receives a video data read command, a video data write command, an audio data write / read command, and other data write / read commands, and the number of sectors requested for each command. Are in the order of video data read command, video data write command, audio data write / read command, and other data write / read commands.
In the time limit setting process, a longer time limit is set for a command having a larger number of requested sectors. A data recording apparatus for writing / reading video data and audio data to / from a plurality of hard disk drives and writing / reading other data to / from a plurality of hard disk drives based on a write / read command received from a host controller. In the internal control method,
A first step of determining the number of sectors required by the command received from the control device, and setting a time limit of a length according to the number of sectors;
A second step of designating the time limit set in the first step and issuing a command corresponding to the command received from the control device to a hard disk drive controller that controls the plurality of hard disk drives;
Of the plurality of hard disk drives, after the command is issued in the second step, a response is returned to the control device based on the result of the writing / reading of only the hard disk drive that has completed the writing / reading process within the time limit. And a third step of performing an internal control method for a data recording apparatus. In the internal control method of the data recording device according to claim 3,
The control device receives a video data read command, a video data write command, an audio data write / read command, and other data write / read commands, and the number of sectors requested for each command. Are in the order of video data read command, video data write command, audio data write / read command, and other data write / read commands.
In the first step, a longer time limit is set for a command having a larger number of requested sectors. A data recording apparatus for writing / reading video data and audio data to / from a plurality of hard disk drives, and writing / reading other data;
In a data recording system including an upper control device that transmits a data write / read command to the data recording device,
The data recording device comprises:
A time limit setting process for determining the number of sectors requested by the command received from the control device, and setting a time limit of a length according to the number of sectors;
A command issuing process for specifying a time limit set in the time limit setting process and issuing a command corresponding to the command received in the command receiving process to a hard disk drive controller that controls the plurality of hard disk drives;
Of the plurality of hard disk drives, a response is returned to the control device based on the result of writing / reading only for the hard disk drive that has completed the writing / reading process within the time limit after issuing the command in the command issuing process. A data recording system comprising a control unit for performing response processing. The data recording system according to claim 5, wherein
The control device transmits a video data read command, a video data write command, an audio data write / read command, and other data write / read commands, and the number of sectors requested for each command is Video data read command, video data write command, audio data write / read command, and other data write / read commands in order.
The data recording system, wherein the control unit of the data recording apparatus sets a longer time limit for a command having a larger number of requested sectors in the time limit setting process.

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