DE102020109434A1 - Storage system - Google Patents

Abstract

A storage system for storing data in a vehicle, the storage system comprising: a controller; a DRAM memory; and a Storage Class Memory - SCM; wherein the data comprises first data of a first category and second data of a second category, wherein the first data comprises newly generated data, and wherein the controller is designed to store the newly generated data in the DRAM memory, the remaining first data in to the SCM and to store the second data in the SCM.

Description

area

The invention relates to a memory system for storing data in a vehicle, which system comprises a DRAM memory and a storage class memory.

background

The main memories used in computers mainly use Dynamic Random Access Memory (DRAM). In the automotive sector in particular, higher demands on the required RAM storage space can be expected in the next few years. This is mainly due to the increase in programs and the data to be processed. The processing of graphic data by image processing and / or rendering in multi-operating system environments, which is often required here, makes it necessary to hold large amounts of data in the main memory. Since DRAM is an expensive technology, high costs are to be expected.

In addition, DRAM has the disadvantage that the memory is volatile. If the DRAM is switched off when the computer is shut down or when a suspend-to-disk standby state is initiated, the data must then be reloaded into the DRAM when the system is reactivated. This means that the system is only available again after a longer boot time. In contrast, if the data is left in a suspend-to-RAM standby state in the DRAM, the system consumes more electrical energy in the standby state.

The object of the invention is to at least alleviate these disadvantages.

Brief description of the invention

The invention is set out in the independent claim. Advantageous refinements can be found in the subclaims.

According to one aspect of the invention there is provided a storage system for storing data in a vehicle, the storage system comprising: a controller; a DRAM memory; and a Storage Class Memory - SCM; wherein the data comprises first data of a first category and second data of a second category, wherein the first data comprises newly generated data, and wherein the controller is designed to store the newly generated data in the DRAM memory, the remaining first data in to the SCM and to store the second data in the SCM.

In one embodiment, the storage system is used as part of an on-board computer in a vehicle to temporarily store one or more programs for data processing and data to be processed. Here, data is understood to mean both programs (including instructions) and data to be processed. It is designed to fulfill the function of a main memory of a computer. In addition, it can be used to take on the function of secondary storage.

A storage class memory can be a flash memory with an oxide-SiN-oxide sandwich structure (SONOS) and / or TaN (TaNOS) as gate, or a ferroelectric RAM, magnetic RAM, resistive RAM, solid electrolyte memory Phase change memory, an organic memory or a carbon nanotube-based memory. Compared to DRAM, storage class memories have higher access times, but are more cost-effective, non-volatile and have a significantly lower power consumption, since regular updates - refreshing - are not required here. Storage class memories have lower access times than flash memories and are equally non-volatile memories.

Data in the first category are data that are particularly bandwidth or latency-critical, i. H. which must be accessed in a short time. The use of a hierarchy of at least two different memory types as main memory makes it possible to use the DRAM for bandwidth and latency-critical data and the storage class memory for the remaining data. This advantageously means that less DRAM memory is required, which leads to cost savings.

The classification of the data into the categories can be implemented in software. In particular, the program code of software, e.g. B. a hypervisor, an operating system and / or a program, comprise commands that assign the data to a category, i. H. specify whether they should be treated as latency-critical and / or bandwidth-critical. In the same way, the data can also be classified as regenerable or non-regenerative. Such commands can cause the controller to store the data accordingly in one of the memories.

The energy consumption in vehicles must be particularly low, especially during a standby state. In addition, it is particularly advantageous in motor vehicles that data processing systems can be used immediately after a voltage supply has been switched on, so that in particular systems for autonomous driving and / or driver assistance systems are immediately available. Thus it is advantageous that the Storage system can be used without a long time delay after the end of an operational interruption, because the software is already in the memory in a format that allows immediate use. This is irrespective of whether the interruption in operation occurred due to a regular switching off and on again when the vehicle was parked, or a technical defect, such as the battery. This eliminates the need for additional software routines to restore the system after a power failure and to initiate and terminate a standby state. This reduces the complexity and the susceptibility to failure of the storage system. Another advantage is that the system does not consume any electrical energy when it is not in use. During this time, the software already stored in the storage class memory is retained because the DRAM memory only contains data that can be regenerated. This means that operation can be resumed without further steps when reactivated.

The DRAM memory can be a low-power double data rate SDRAM. This also keeps the electrical power consumption low during operation.

In one embodiment of the invention, the data that can be newly generated are data that can be newly generated within a predetermined, maximum processing time. Data of the first category that cannot be regenerated are in particular runtime variables that are required during data processing and in particular contain user-defined settings.

The maximum processing time is a maximum time that can elapse before the storage system can be used again after the business interruption. It depends on the hardware and software equipment used on board the vehicle. If the storage system is used, for example, to store data when evaluating images from a camera attached to or in the vehicle, the maximum processing time is the time in which the first camera image is recorded and processed. This maximum processing time is typically on the order of a few seconds. It is therefore relevant for the start of operation and can therefore be longer than the maximum access times defined below, which relate to the maximum tolerable delays during operation.

In a further embodiment of the invention, the newly generated data include data that were generated by a sensor attached to or in the vehicle and / or data that were generated using this data.

Data processing on board a vehicle typically includes the evaluation of data supplied by a large number of sensors. These can in particular be cameras for visible and / or infrared light, radar devices or devices for satellite-based navigation. These data are generated and processed "live", i.e. generated by the sensor at short intervals, processed by processing software and used by displaying the results of the processing to the driver and / or activating actuators that influence the driving parameters. For example, data from a camera can be filtered to make obstacles recognizable. According to the invention, the newly generated data, d. H. Both the raw data and the data already processed in an intermediate step are stored in the DRAM memory, since the previously generated data are no longer required after an interruption in operation. In contrast, the processing software is stored in the non-volatile storage class memory.

In a further embodiment of the invention, the newly generated data include data that was received via a network from a computer outside the vehicle.

Data generated outside the vehicle is also processed on board a vehicle. These are, in particular, sensor and traffic data that are sent to the vehicle by other vehicles, for example to warn of a critical traffic situation. These data can e.g. B. be transmitted via vehicle-to-everything (V2X). In addition, data from a cloud, such as traffic data, e.g. B. via cellular networks, e.g. B. LTE or 5G, transmitted to the vehicle and processed in the vehicle using the storage system.

In a further embodiment of the invention, the first category is formed by data that must be readable from the memory within a predetermined, maximum access time.

If only those data are stored in the DRAM memory for which access with a short access time is required, the DRAM memory can be dimensioned relatively small. This will reduce costs. The maximum access time can assume a value in the order of magnitude of a few tens of nanoseconds, which corresponds to the access times for DRAM memories.

In a further embodiment of the invention, the first category comprises data that were generated by a sensor attached to or in the vehicle. For example, images from a camera can be evaluated to identify obstacles identify and report to the driver. The use of the DRAM memory offers a speed advantage because the DRAM memory offers a short access time and a high bandwidth.

In a further embodiment of the invention, the second category comprises data which represent at least parts of runtime environments of programs.

These runtime environments include both program instructions and data that are created at runtime, such as settings specified by the user. According to the invention, these data are classified in the second category, unless particularly fast access is required. This saves DRAM memory and reduces costs.

In a further embodiment of the invention, the second category comprises data that represent one or more operating systems in a virtual environment.

Such environments and the operating systems operated by them typically have a high memory requirement. A large part of the data to be saved is not critical to performance. The storage system is designed to store this data in the storage class memory. This reduces the need for DRAM memory and costs.

In a further embodiment of the invention, a storage system is created which further comprises a third electronic memory, wherein the data further comprise third data of a third category, and wherein the controller is further designed to store the third data in the third memory.

Like the first and the second memory, the third electronic memory also has no moving mechanical components and is therefore robust against vibrations. For the third electronic memory, a technology can be used that is more cost-effective than DRAM and storage class memory, for example flash memory technology. The third electronic memory stores data that have less stringent requirements in terms of bandwidth and access time and therefore do not have to be stored in the storage class memory. In addition, the flash memory can take on the role of secondary storage. This saves further costs.

In a further embodiment of the invention, the second category is formed by data that must be readable from the memory within a second predetermined maximum access time.

The second maximum access time is typically on the order of 100 nanoseconds to one microsecond. According to one embodiment, the third data are stored in the third electronic memory, since they are not required within this time. For example, the on-board computer can have different operating modes, with different sets of instructions for each operating mode, e.g. B. different program libraries are required. The program libraries that are not used in each case can thus be stored in the third electronic memory, while the program libraries used are stored in the storage class memory. The access time of the second electronic memory that is above the second maximum access time thus only limits the switching between the operating modes. At the same time, cost savings are achieved because less storage class memory is required.

In a further embodiment of the invention, the third category comprises data that can be used to reset the memory system to a factory state and / or for a software update.

During the service life of the on-board computer and the storage system, a cold start with subsequent commissioning of the software environment is required only once, namely directly after the installation of the system, during the production of the vehicle. Hypervisor, operating systems and application software are only set up and put into operation once. Over the life of the vehicle, operational interruptions do not lead to a reconfiguration. If, as an exception, a malfunction occurs that requires reconfiguration, this can be done using data stored in the third electronic memory. This makes the process easier because the software does not have to be loaded from an external storage medium.

In addition, the memory can be used particularly advantageously to store software that updates the software during the life of the system (over-the-air updates, OTA updates). As part of such an update, the different software versions are also stored in the third electronic memory, which has sufficient storage capacity for this purpose. In contrast, the storage class memory can be dimensioned smaller, which saves costs.

Figure list

• die 1 ein beispielhaftes Speichersystem gemäß der Erfindung;
• die 2 ein Flussdiagramm, das die Zuordnung der Daten zu den Speichertypen darstellt;
• die 3 einen Bordcomputer, der einen Prozessor und das Speichersystem aufweist; und
• die 4 ein Anwendungsbeispiel, in dem Bilddateien aufgenommen und verarbeitet werden.

Exemplary embodiments of the invention are described in more detail with reference to the accompanying drawings. Show it

• the 1 an exemplary storage system in accordance with the invention;
• the 2 a flowchart showing the assignment of the data to the storage types;
• the 3 an on-board computer having a processor and the memory system; and
• the 4th an application example in which image files are captured and processed.

Figure description

1 shows an exemplary storage system 100 according to the invention. The controller 102 controls a DRAM memory 104 , a storage class memory 106 and another electronic memory 108 . In one embodiment, the control is carried out by the controller in whole or in part in accordance with the in 2 steps shown.

2 Figure 3 shows a flow chart showing the steps of a method 200 represents according to one embodiment of the invention. First of all, the data to be saved is received by the controller 202 . These can be instructions as well as data to be processed. For example, images from a camera or other data generated by sensors can be assigned to the first category and classified as being newly generated. Program code of an operating system can be assigned to the second category, for example. Before the data is saved, a check is carried out to determine which category the data to be saved has been assigned to 204 . Are the data assigned to the first category 206a , it is checked whether they are classified as regenerable. If this is the case, the data are stored in the DRAM memory 210 . Otherwise they are saved in the storage class memory 212 . Are the data of the second category 206b assigned, they are always saved in the storage class memory 212 . Are the data of the third category 206c assigned, they are stored in a further electronic memory 214 .

3 shows an on-board computer 300 having a processor 302 and having the storage system and running a plurality of operating systems in a virtual environment. At the beginning of the life of the vehicle, ie when the vehicle is manufactured after the storage system and other electronic components have been installed, the software 306 - Comprising a hypervisor, the operating systems and programs - loaded into the storage class memory and started. From this point on, this software is executed by the on-board computer and remains in the memory. The software contains commands that assign data to the categories and classify it as regenerative or non-regenerative. In particular, sensor data 304 are stored in the DRAM memory. Independently of this, a copy of the software in the factory state is stored 308 as a backup copy in the further electronic memory.

4th shows an application example 400 . Image data are recorded by an infrared camera. These image data are processed by a program for evaluating the image data. This assigns the received from the camera 406 Assigns image data to the first category, classifies it as regenerative and causes the data to be saved 408 . This can be done in that the program code contains suitable commands for this purpose. In response to this, the controller stores the data - as described above - in the DRAM memory 410 . In a further processing step, the program gives the command to load the image 412 , and the storage device loads the image from the DRAM memory 414 . An algorithm searches for objects in the image that can be identified as obstacles 416 . The resulting intermediate data - z. B. a filtered version of the image, coordinates that describe a position of the object, or the information as to whether there is an obstacle in the image - are possibly also assigned to the first category by the program using the appropriate commands, classified as newly generated and saved. Finally, the result, for example that the driver must be warned of an obstacle, is sent to a data output device, e.g. B. an acoustic signal generator output 418 . Using the DRAM ensures that processing takes place in a short time and the warning of the obstacle can be issued promptly.

List of reference symbols

100

Storage system

102

Controller

104

DRAM memory

106

Storage class memory

108

Further electronic storage

200

Save the data

202

Enter the data to be saved

204

Category?

206a

First category

206b

Second category

206c

Third category

208

Can data be regenerated?

210

Store in DRAM memory

212

Save in storage class memory

214

Save in further electronic memory

300

Board computer

302

processor

304

Sensor data

306

software

308

Factory software

400

Method for evaluating signals from a camera

402

Steps to be executed by the processor

404

Steps to be executed by storage system

406

Receiving an image from a camera

408

Classification, classification, storage command

410

Save on computer

412

Command to load an image

414

load

416

Process the image

418

Output of a warning signal

Claims (17)

A storage system (100) for storing data in a vehicle, the storage system comprising: a controller (102); a DRAM memory (104); and a storage class memory - SCM (106); wherein the data comprises first data of a first category and second data of a second category, wherein the first data comprises newly generated data, and wherein the controller is designed to to store the newly generated data in the DRAM memory (210), store the remaining first data in the SCM (212), and store the second data in the SCM (212). Storage system according to Claim 1 , the newly generated data being data which can be newly generated within a predetermined processing time. Storage system according to Claim 1 or 2 , the newly generated data including data that can be generated by a sensor arranged in or on the vehicle. Storage system according to one of the preceding claims, wherein the data which can be newly generated comprise such data which can be generated using data which were previously generated by a sensor mounted in or on the vehicle. Storage system according to one of the preceding claims, wherein the data which can be newly generated comprise data which have been received via a network from a computer outside the vehicle. Memory system according to one of the preceding claims, wherein the data of the first category are formed by data which must be readable from the memory within a predetermined access time. Storage system according to any one of the preceding claims, wherein the data of the first category comprises data generated by a sensor mounted on or in the vehicle. Storage system according to one of the preceding claims, wherein the data of the second category comprises data which represent at least part of a runtime environment of a program. Storage system according to one of the preceding claims, wherein the data of the second category comprises data representing one or more operating systems in a virtual environment. Storage system according to one of the preceding claims, wherein the storage system further comprises a third electronic memory (108), wherein the data further comprises third data of a third category, and wherein the controller is further designed to store the third data in the third memory ( 214). Storage system according to Claim 10 , wherein the data of the third category comprises data which do not have to be retrievable or available within a second predetermined access time. Storage system according to Claim 10 or 11 , the data of the third category comprising data that can be used to reset the storage system to an initial or factory state and / or that can be used to update software that can be stored in the storage system. Method for storing data in a storage system in a vehicle, wherein the data comprising first data of a first category and second data of a second category, the first data comprising regenerative data, the method comprising: storing the regenerative data in a DRAM memory; Storing the remaining first data in a storage class memory, SCM; Store the second data in the SCM. Procedure according to Claim 13 , further comprising: assigning data to the first category which must be readable from the memory within a predetermined access time and / or which were generated by a sensor attached to or in the vehicle. Procedure according to Claim 13 or 14th , further comprising: assigning data to the second category which represent at least part of a runtime environment of a program and / or which represent one or more operating systems in a virtual environment. Method according to one of the Claims 13 until 15th , further comprising: assigning data to a third category which do not have to be retrievable or available within a second predetermined access time and / or which can be used to reset the storage system to an initial or factory state; and storing data of the third category in a third electronic memory. Computer program product, comprising a computer-readable storage medium comprising instructions which, when the program is executed by a computer, cause the computer to use the method according to one of the Claims 13 - 16 to execute.

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