DE102018210711A1 - Method and computer system for prioritized file access, computer program and computer readable data carrier - Google Patents

Abstract

The invention relates to a method for prioritized file access in a computer system with an operating system comprising a directory structure provided by the operating system, a storage medium (1), a block virtualization system (2), and at least a first block device (A), which is accessed via a block virtualization system (2) accesses the storage medium (1), a first mounting point (X), which is hooked into the directory structure and points to the first block device (A), at least one second block device (AA) which is connected to the storage medium (2) via a block virtualization system (2) 1) and a second mount point (Y), which is hooked into the directory structure and points to the second block device (AA), is included, with a first file in the storage medium (1) to which the first block device (A) and the second block device (AA) accesses, is saved, and access to the first file via the first mount point (X ) with a first priority and access to the first file via the second mount point (Y) with a second priority different from the first priority.
The invention further relates to a computer system for prioritized file access, a computer program and a computer-readable data carrier

Description

The invention relates to a method for prioritized file access in a computer system with an operating system comprising a directory structure provided by the operating system, a storage medium, a block virtualization system, at least a first block device which accesses the storage medium via a block virtualization system, a first mount point, which is in the directory structure is mounted and points to the first block device. The invention further relates to a computer system for prioritized file access, a computer program and a computer-readable data carrier.

Current file systems do not allow long and persistent access, such as reading a large file, to do a more important process first.

Incoming requests for read and write access are processed in the order in which they arrive at the respective file system software instance. This is also known as the “FIFO First In - First Out” principle. Files that are saved first are also removed from memory first. The queue in IT is based on the FIFO principle. The files are retrieved in the order in which they were previously stored.

However, there is no prioritization of accesses or requests to be processed and no interruption of the request currently being processed.

In many cases, however, it is necessary to prefer certain accesses or data streams over others.

This is the case, for example, for reading inquiries that are to be carried out as quickly as possible or in a certain time grid, for example in the case of safety-critical functionalities, such as a representation of a vehicle environment, in the form of a distance warning or else audio or video playback of the vehicle environment. These read requests are delayed by requests that are already waiting, including access requests that have no or low requirements for prompt execution, but arrive earlier in the file system. Furthermore, these requests are delayed by requests that are currently being processed. This can lead to a significant delay, especially for read or write accesses that access large amounts of data.

The previous solutions to such problems are complex configurations or implementations, for example the so-called caching for an audio / video playback. However, this requires more RAM. Another option is to configure start times or to split large amounts of data for reading / writing into smaller units. However, this results in higher costs.

The US 20080126645 A1 discloses a memory system and data input / output control method, for example, one suitable for use in a memory system in which a host device performs processing for various types of work using application programs. The storage system performs data input / output processing for the priority targets and the non-priority target group at the frequencies corresponding to the respective processing percentages determined by the processing percentage determination unit.

The US 6253260 B1 discloses a system and method for processing a file access request (DAR). A processing unit, such as. B. a memory controller receives a DAR indicating data to be returned on a channel, such as a channel connected to a host system, and priority information for the received DAR. The processing unit retrieves the requested data for the received DAR from a memory area, such as a cache or a random access memory device (DASD), and determines whether there is a queue of data entries indicating retrieved data for DARs to be transmitted on the channel. The queued DARs contain priority information. The processing unit processes at least one data entry in the queue which has priority information for the data entry and priority information for the received DAR in order to determine a position in the queue for the received DAR. The processing unit then indicates that the received DAR is in the designated position in the queue and processes the queue to select retrieved data to be transmitted on the channel to the host system.

In the DE 112008003256 T5 determines whether a file is to be placed on a slower drive in a logical storage volume or on a faster drive in the logical storage volume, and a user need not be aware of whether the file was placed on the slower drive or the faster drive.

In the DE 10032962 A1 describes a distributed file system with autonomous disks. The file system includes autonomous disks that store application data. Legacy attribute disks store file system metadata and directory structure. The directory structure is stored on the legacy attribute disks in the original file system. One of the filesystem clients is used as a configuration manager to monitor access to the system. The distributed file system uses agents to support real-time applications and competing read / write access to files.

The US 4616338 discloses a device for temporarily storing data, organized according to a queue according to the "first in-first out" principle, comprising a read-write buffer with random access and a control system, the device having a first and a second output buffer register, which are connected in series after the buffer, and which also has an input buffer register upstream of the buffer.

The object of the invention is therefore to provide an inexpensive method and a computer system with which prioritized file or data access can be accomplished, as well as a corresponding computer program and a corresponding computer-readable data carrier.

The object is achieved by a method for prioritized file access with the features of claim 1, a computer system with the features of claim 10 and a computer program with the features of claim 18 and a computer-readable data carrier with the features of claim 19.

The subclaims list further advantageous measures which can be combined with one another as desired in order to achieve further advantages.

The object is achieved by specifying a method for prioritized file access in a computer system with an operating system comprising a directory structure provided by the operating system, a storage medium, a block virtualization system, at least a first block device which accesses the storage medium via the block virtualization system, a first mount point, which is attached to the directory structure and points to the first block device.

Within the scope of the invention, at least one second block device, which accesses the storage medium via the block virtualization system, and a second mount point, which is hooked into the directory structure and points to the second block device, is included, with a first file in the storage medium, to which the first Accesses the block device and the second block device, is stored, and the first file is accessed via the first mount point with a first priority and the first file is accessed via the second mount point with a second priority that differs from the first priority.

In other words, a memory access layer, in which the block devices are arranged, is configured between the block virtualization system and an application layer in such a way that, instead of a block device, several block devices are made available for the storage medium that is only physically present and contains the file system, for example the file system FS_PA become. These can be prioritized among one another in the memory access layer in which the block devices are arranged.

In this case, an application can also be provided as a priority, for example a memory prefetch, a normal application access priority or a prioritized application access. Memory anticipation is a technique used by computer processors to improve execution performance by fetching instructions or data from their original slower memory to faster local memory before they are actually needed. Files can also be individual data.

A block device, also called block-oriented device, transfers data into existing memory blocks of a storage medium and is therefore often used for parallel data transfers. Block devices have their own operating system buffer.

The relationship of file system instances to specific mount points within a file system or a root file system is usually handled in the file system layer. For example, a file system FS_PA is assigned to the storage medium. If several storage media are available in one computing unit, all instances have a file system. If necessary, the storage medium can be divided into partitions, each of which is also assigned its own file system.

A directory structure is the hierarchical structure of the file system from a single computer.

According to the invention, it was recognized that only the insertion of suspension points within the same file system, for example the file system FS PA, would not lead to the desired effect. While the path within the file system layer is being resolved, a virtual file system switch only resolves access to the same parts of the storage medium, even though they are given via different paths / mount points. The block virtualization system, for example the block driver, therefore does not receive any information about the requested priority for the file system access below the file system. According to the invention, it was also recognized that the information about the various priorities must be made available as far as the storage medium. The method provides different block devices for the storage medium, but all of them are assigned to the same physical storage medium or the same physical partition of the storage medium. This allows access to the same file in the storage medium with a different priority.

According to the invention, it was also recognized that the file system contains metadata that is only available once and that must be made available to the file system by all block devices.

If access to a file is now carried out, for example the first file is accessed under the mount point with low priority, and the system accesses a second file with higher priority than the low priority, which is arranged under the mount point with high priority, so the execution of the first file can be interrupted and the second file can be executed first. In addition, regardless of the "queue", high-priority file accesses are always carried out before lower file accesses, regardless of the "arrival / request" of the file access. The invention can therefore differentiate between security-relevant and non-security-relevant data.

The invention has the effect that the block virtualization system accesses the entire storage medium, but makes a different (virtual) block device available to the higher-level instances or layers for the same physical storage medium.

• /dev/virt-blockdevice-A
• /dev/virt-blockdevice-AA
• /dev/virt-blockdevice-AAA

The virtual file system thus sees the storage media:

• / Dev / virt-block device-A
• / Dev / virt-block device-AA
• / Dev / virt-block device-AAA

The block virtualization system preferably has a table, in which it is determined how the block virtualization system treats accesses that come in via the various mount points with one another.

The invention makes it possible to provide an HMI (Human Machine Interface) interface with prioritized access to one and the same file, for example in an integration platform. For example, a driver assistance system simply accesses this file via the first mount point with first priority. Once the file has been executed and, for example, the safety-relevant aspect has passed, the driver assistance system can again access the same file via another mount point with lower priority.

This makes it possible to provide a standard file interface, for example POSIX, which does not offer access priorities, with differently prioritized file access, for example for electronic control units or apps, etc.

The multiple, redundant access also enables secure data use.

By means of the invention, the file accesses can be optimized for the boot process, for example by delaying the start of less important applications, etc.

Furthermore, a second file is preferably provided, which is executed via the second mount point with the second priority, the execution being interrupted when the first file is accessed via the mount point with the first priority. The first priority is higher than the second priority. As a result, security-relevant data can be accessed preferentially and less prioritized accesses with less security-relevant data can be interrupted in the short term in order to obtain the security-relevant data as quickly as possible.

In a preferred embodiment, a first file is provided, which is executed via the second mount point with the second priority, the execution being interrupted when the first file or parts of the first file are accessed via the first mount point with the first priority. When a file is executed via a mount point with a lower priority, execution is therefore always interrupted as soon as a higher-priority file access arrives.

The directory structure is preferably in the form of a hierarchical directory structure formed as a tree structure with a root directory. The directory structure for storing files and / or directories is formed in each instance.

The storage medium is furthermore preferably configured as at least one storage block. A memory block, also called a data block, represents the smallest unit of a storage medium that can be read or written in one access.

In a preferred embodiment, the storage medium has at least one partition, the memory block being assigned to the at least one partition. The memory block can also have several partitions.

In a further preferred embodiment, at least a third block device which accesses the storage medium and a third mount point which is hooked into the directory structure and points to the third block device are included, the first file being stored in the storage medium and the access to the first file is made via the third mount point and the third block device with a third priority, the third priority being designed differently from the first priority and the second priority. In a preferred further embodiment, the first priority is made higher than the second priority and the second priority is made higher than the third priority.

For example, the file example.sql is given here. This is attached to the directory structure by three different attachment points. The first mount point / highprio / opt / hmi has a first high priority. The second mount point / opt / hmi has a second priority, which is lower than the first priority and is set, for example, as the standard priority. The third mount point / prefetch / opt / hmi is intended for background applications and has a third priority, which is lower than the first and second priority. An application layer can therefore access the file with a first priority under /highprio/opt/hmi/beipsiel.sql, with a second priority under /opt/hmi/beispiel.sql and with a third priority under prefetch / opt / hmi / example .sql can be accessed to run the example.sql file.

Multiple mount points with multiple priorities can also be provided.

A third file is particularly preferably provided, which is executed via the third mount point with the third priority, the execution when accessing the first file via the first mount point with the first priority or when accessing the first file via the second mount point with the second priority is interrupted. The execution of a file is interrupted whenever there is a higher priority access to another file.

Furthermore, the storage medium is preferably designed as an embedded multimedia card (eMMC), that is to say as an embedded multimedia card. An eMMC (embedded multimedia card) is a standard based on flash memory for a universally applicable, integrated mass storage device. These are particularly inexpensive.

In an additional preferred embodiment, a VFS (Virtual File System, VFS) switch is provided, which hooks the suspension points into the directory structure. A VFS switch provides programs on a VFS layer with a uniform interface for application programming in order to access the different mounting points. The VFS switch is arranged on a VFS (layer) layer.

The block virtualization system preferably has a table in which it is determined how the block virtualization system treats accesses which come in via the various mount points with one another and thereby defines the priorities. The VFS (layer) layer preferably remains untouched.

The operating system is further preferably configured as a Unix or Linux-based operating system.

It can advantageously be seen that when a write access to the storage medium is blocked by a first mount point, the write access to the storage medium is blocked by a second mount point. This also applies the other way round, that is to say that in the event of a write access to the storage medium by a second mounting point, the writing access to the storage medium is blocked by a first mounting point.

Furthermore, it can advantageously be provided that when a write access to the storage medium is made, a different, second mount point is unmounted by a first mount point. This means that when sending or receiving data from a file, the system always waits (blocks) until the respective write access is completed.

For the subsequent synchronization of the storage medium, synchronization mechanisms are preferably used.

Furthermore, the object is achieved by specifying a computer system with an operating system for executing a method as described above, for executing a prioritized file access, comprising a directory structure provided by the operating system, a storage medium, a block virtualization system, at least one first block device which accesses the storage medium via the block virtualization system, a first mount point which is hooked into the directory structure and points to the first block device, wherein
at least a second block device, which accesses the storage medium via the block virtualization system, and a second mount point, which is hooked into the directory structure and points to the second block device, is provided, with a first file in the storage medium, to which the first block device as well the second block device accesses, is stored, and the first file is accessed via the first mount point with a first priority and the first file is accessed via the second mount point with a second priority different from the first priority.

Like the process, the computer system can be used with file systems which are freely available on the market without having to be adapted or changed. The invention is therefore independent of the file system used and for existing standard file systems and standard operating systems for file system access, e.g. POSIX can be used.

A second file is preferably provided, which is executed with the second priority via the second mount point, the execution being interrupted when the first file is accessed via the mount point with the first priority.

The storage medium further preferably comprises at least one storage block. In a further preferred embodiment, at least a third block device, which accesses the storage medium, and a third mount point, which is hooked into the directory structure and points to the third block device, are included, the first file being stored on the storage medium, and the access to the first file is made via the third mount point and the third block device with a third priority, the third priority being different from the first priority and the second priority. More preferably, the first priority is higher than the second priority and the second priority is higher than the third priority.

A third file is advantageously provided, which is executed with the third priority via the third mount point, the execution having access to the first file via the first mount point with the first priority or when accessing the first file via the second mount point with the second priority Priority is interrupted.

In a further preferred refinement, write access to the storage medium is blocked by a second mounting point in the event of write access to the storage medium by a first mounting point. In the case of write access to the storage medium, the other, second mount point is preferably unmounted by a first mount point.

The advantages of the method can also be applied to the computer system.

Another object of the invention relates to a computer program comprising commands which, when the program is executed by the computer, cause the computer to carry out the method as described above.

Another object of the invention relates to a computer-readable data carrier on which the computer program as described above is stored.

• 1: ein erstes Ausführungsbeispiel der Erfindung,
• 2: ein zweites Ausführungsbeispiel gemäß der Erfindung,
• 3: ein drittes Ausführungsbeispiel gemäß der Erfindung.

Further features, properties and advantages of the present invention will become apparent from the following description with reference to the accompanying figures. It shows schematically:

• 1 : a first embodiment of the invention,
• 2 : a second embodiment according to the invention,
• 3 : a third embodiment according to the invention.

Although the invention has been illustrated and described in detail by the preferred exemplary embodiment, the invention is not restricted by the disclosed examples. Variations on this can be derived by those skilled in the art without departing from the scope of the invention as defined by the following claims.

1 shows a first embodiment of the invention. The computer system and method according to the invention has a hierarchical directory structure and - here, for example, a file with a file name animationxyz.mp4. A hierarchical directory structure is the hierarchical form of a file system.

1 shows a storage medium 1 , The storage medium 1 can be designed as an eMMC (emmedded MultiMedia Card) or as a hard disk or as another storage medium. The storage medium 1 assigns a partition in this example K with the file system FS_PA. The file system can also be referred to as a file system. The partition K comprises several data blocks also called memory blocks.

Furthermore, a first block device A , which is provided on the storage medium 1 or on the memory blocks of the partition K shows. That is, the block device A is on the physical address, here on the memory blocks of the partition K displayed. This is done with a block virtualization system 2 , that is, a memory management unit / device driver. With block virtualization, the memory blocks of a storage medium 1 stored in a table, which is also referred to as a "mapping table". This shows where exactly certain memory blocks are located. The block virtualization thus separates the block device from the physical memory, so that this memory can be accessed regardless of the physical storage medium. The block virtualization system 2 is on the memory access layer 7 arranged.

The physical address of the partition's memory blocks K is therefore based on the "block device A "Held. There is also a second block device AA , which is provided on the storage medium 1 or on the memory blocks of the partition K shows. There is also a third block device AAA , which is provided on the storage medium 1 or on the memory blocks of the partition K shows. The first block device A , the second block device AA and the third block device AAA are with three mount points, so-called MountPoints X . Y . Z connected.

Through a VFS switch 3 (Engl. Virtual File System, virtual file system) on a VFS (layer) layer 4 , the mount points X . Y . Z mounted in the hierarchical directory structure and are visible there. The VFS switch 3 can link the block devices A . AA . AAA with the mount points X . Y . Z , accomplish.

VFS Switches 3 are application programming interfaces which “unmount” and “mount” the mount points X . Y . Z take. The mount points X . Y . Z are thus mounted in a directory structure of the computer, that is, the previous directory structure is therefore around the mount points X . Y . Z extended. The mount points X . Y . Z are specified in a filesystem table, in which properties can also be predefined. Here are about the respective mount points X . Y . Z The different priorities or the different use cases are assigned, that is to say that by mounting on a specific mounting point X . Y . Z , the assignment to the priorities / use cases. The VFS switch 3 and the assignment of file system instances to different mount points X . Y . Z remain unchanged, however, as provided by the respective operating system, that is, there is no change in the file system functionality and no change by the VFS switch 3 , This means that the whole VFS (layer) layer 4 remains untouched. The prioritization takes place in the block virtualization system 2 and the memory access layer 7 ,

One use case bundles all possibilities that can arise when a user tries to achieve a certain goal with the help of a method / computer system, i.e. For example, one use case describes how a user uses a system to achieve a specific goal.

The first mount point X becomes a first priority, the second mount point Y a second priority and the third mount point Z a third priority is assigned, the first priority being greater than the second priority and the second priority being greater than third priority.

• /X/res/video/animationxyz.mp4
• /Y/res/video/animationxyz.mp4
• /Z/res/video/animationxyz.mp4

Here the file animationxyz.mp4 in the directory path "/ res / video / animationxyz.mp4" is now on the mount points X . Y . Z mounted. This now results in three different directory paths with three different priorities:

• /X/res/video/animationxyz.mp4
• /Y/res/video/animationxyz.mp4
• /Z/res/video/animationxyz.mp4

Through these paths, the user or a system, for example a driver assistance system, can access the animationxyz.mp4 file with different priorities. The file can be accessed from an application layer 5 through an application programming interface 6 (API) can be accessed.

Access via the mount point / X / res / video / animationxyz.mp4 has the highest priority. Access to other files or the same file is interrupted if it is carried out with a lower priority access.

Access is from the storage access layer 7 prioritized out.

Because the files of the various block devices A . AA . AAA to the different mount points X . Y . Z be set, or the block devices A . A . AAA the different mount points X . Y . Z assigned, access to the animationxyz.mp4 file ends up through the various mount points X . Y . Z with the corresponding block devices A . AA . AAA on the partition K of the storage medium 1 , Access to the storage medium 1 is therefore subject to different priorities.

A write access to the storage medium 1 done by a block device A or AA or AAA , If write access by different block devices is possible, write access is either blocked entirely or there is one exception Block device through which write access is to take place, all other block devices using their mount point X . Y . Z unmounted.

In this example, the storage medium is 1 trained here as eMMC.

You can also have more than three block devices with more than three mount points on the partition K of the storage medium 1 access, be provided.

If access to a file with low priority is now carried out, for example to a first file under the third mount point Z accessed, and the system accesses a second file, which is under the first mount point X is arranged, the execution of the first file is interrupted and the second file is executed first.

Thus, for example, a driver assistance system can prioritize the animationxyz.mp4 file via the file name and the path name, in this case via the first mount point X and access the path name /X/res/video/animationxyz.mp4 if this file or data is currently important for security-related aspects. Other less highly prioritized accesses are then interrupted.

2 shows a second embodiment of the invention. Here is an application programming interface 6 called a file important.sql. The file was created as below 1 described, via the mount points X . Y . Z and the block devices A . A . AAA in one partition K of the storage medium 1 saved.

The file is generated by a driver assistance system, for example, via the application programming interface 6 called with highest priority. The VFS switch 3 reaches (8) over the first mounting point X on the block device A to. This in turn accesses (8) via the block virtualization system 2 to the partition K and the file important.sql is executed. Access from the application programming interface 6 to the partition K over the first mount point X are with the reference symbol 8th characterized. That is, as long as access continues, data from the executed file becomes important.sql to the application programming interface 6 returned, this is with the reference number 9 characterized.

While the driver assistance system is being accessed via the application programming interface 6 and the first mount point X , grabs the application programming interface 6 again to a file less important.sql. The file is generated by the driver assistance system via the application programming interface 6 called with lowest priority. The VFS switch 3 reaches (10) over the third mount point Z on the block device AAA to. This tries, via the block virtualization system 2 to the partition K to access to run the less important.sql file; however, it is from the block virtualization system 2 , that is, the memory access layer 7 who denied access. This access, here with the reference symbol 10 is denied until the execution of the important.sql file has ended; here as an ending point 11 characterized. Then the file less important.sql is executed and data of the executed file less important.sql are returned, here with the reference symbol 12 characterized.

3 shows a third embodiment of the invention. Here is an application programming interface 6 called a file less important.sql. The file was created as below 1 described, via the mount points X . Y . Z and the block devices A . A . AAA in one partition K of the storage medium 1 saved.

The file is generated, for example, by a driver assistance system via the application programming interface 6 called with lowest priority. The VFS switch 3 reaches over the third mount point Z on the block device AAA to. This in turn accesses the block virtualization system 2 to the partition K and the program less important.sql is executed. Access from the application programming interface 6 to the partition K over the third mount point Z are with the reference symbol 10 characterized.

That is, the data of the executed file less important.sql becomes the application programming interface 6 returned, this is with the reference number 12 characterized.

During execution, the application programming interface 6 called a file important.sql. The file was created as below 1 described, via the mount points X . Y . Z and the block devices A . A . AAA in one partition K of the storage medium 1 saved. The file is generated by the driver assistance system via the application programming interface 6 with the highest priority over the first mount point X and the block device A called. The VFS switch 3 reaches over the first mount point X on the block device A to. This reaches over the block virtualization system 2 to the partition K to run the important.sql file. The storage medium 1 , that is the partition K pauses at a break point 13 in this case, the execution of the file less important.sql starts immediately and starts the execution of the Important.sql file. This access, here with the reference symbol 8th , is executed until the execution of the important.sql file has ended; here as the end time 14 characterized. Then the file less important.sql is executed again.

LIST OF REFERENCE NUMBERS

1

storage medium

2

Block virtualization system

3

VFS switch

4

VFS layer structure

5

application layer

6

application programming

7

Memory access layer

8th

Views

9

Returned data from 8

10

Views

11

termination point

12

Returned data from 10

13

breakpoint

14

end time

X, Y, Z

Mount Points

A, AA, AAA

block devices

K

partition

FS PA

file system

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• US 20080126645 A1 [0008]
• US 6253260 B1 [0009]
• DE 112008003256 T5 [0010]
• DE 10032962 A1 [0011]
• US 4616338 [0012]

Claims (19)

Method for prioritized file access in a computer system with an operating system comprising a directory structure provided by the operating system, a storage medium (1), a block virtualization system (2), at least a first block device (A) which is connected to the storage medium (1) via a block virtualization system (2) ) accesses a first mount point (X), which is hooked into the directory structure and points to the first block device (A), characterized in that at least one second block device (AA) which is connected to the storage medium (1) via a block virtualization system (2) ) and a second mount point (Y), which is hooked into the directory structure and points to the second block device (AA), is included, with a first file in the storage medium (1) to which the first block device (A) and the second block device (AA) accesses, is stored, and access to the first file via the first mount point (X) m it with a first priority and the first file is accessed via the second mount point (Y) with a second priority different from the first priority. Procedure according to Claim 1 , characterized in that a second file is provided, which is executed with the second priority via the second mount point (Y), the execution being interrupted when the first file is accessed via the first mount point (X) with the first priority. Procedure according to Claim 1 or 2 , characterized in that a first file is provided which is executed via the second mount point (Y) with the second priority, the execution when the first file or parts of the first file are accessed via the first mount point (X) with the first priority is interrupted. Method according to one of the preceding claims, characterized in that at least one third block device (AAA), which accesses the storage medium (1), and a third mount point (Z), which is hung in the directory structure and on the third block device (AAA) shows, is included, the first file being stored in the storage medium (1) and the first file being accessed via the third mount point (Z) and the third block device (AAA) with a third priority, the third priority of the first priority and the second priority are formed differently. Procedure according to Claim 4 , characterized in that the first priority is formed higher than the second priority and the second priority higher than the third priority. Procedure according to one of the Claims 4 to 5 , characterized in that a third file is provided which is executed via the third mount point (Z) with the third priority, the execution when accessing the first file via the first mount point (X) with the first priority or when accessing the first file is interrupted with the second priority via the second mount point (Y). Method according to one of the preceding claims, characterized in that the operating system is designed as a Unix or Liunx-based operating system. Method according to one of the preceding claims, characterized in that in the event of a write access to the storage medium (1) by a first mount point (X), the write access to the storage medium (1) is blocked by a second mount point (Y). Method according to one of the preceding claims, characterized in that in the case of write access to the storage medium (1), a different, second attachment point (Y) is removed by a first attachment point. Computer system with an operating system for executing a method for executing a prioritized file access, according to one of the preceding claims, comprising a directory structure provided by the operating system, a storage medium (1), a block virtualization system (2), at least a first block device (A), which a block virtualization system (2) accesses the storage medium (1), a first mount point (X), which is hooked into the directory structure and points to the first block device (A), characterized in that at least one second block device (AA), which via a block virtualization system (2) accesses the storage medium (1), and a second mount point (Y), which is hooked into the directory structure and points to the second block device (AA), is provided, a first file in the storage medium (1) , which the first block device (A) and the second block device (AA) access, is stored, u nd access to the first file via the first mount point (X) with a first priority and access to the first file via the second Mount point (Y) with a second priority different from the first priority. Computer system after Claim 10 , characterized in that a second file is provided which is executed with the second priority via the second mount point (Y), the execution being interrupted when the first file is accessed via the first mount point (X) with the first priority. Computer system according to one of the Claims 10 to 11 , characterized in that the storage medium (1) comprises at least one storage block. Computer system according to one of the preceding Claims 10 to 12 , characterized in that at least a third block device (AAA), which accesses the storage medium (1), and a third mount point (Z), which is hooked into the directory structure and points to the third block device (AAA), is included, whereby the first file is stored in the storage medium (1) and the first file is accessed via the third mount point (Z) and the third block device (AAA) with a third priority, the third priority being the first priority and the second Priority is different. Computer system after Claim 13 , characterized in that the first priority is higher than the second priority and the second priority is higher than the third priority. Computer system after Claim 13 or 14 , characterized in that a third file is provided which is executed via the third mount point (Z) with the third priority, the execution when accessing the first file via the first mount point (X) with the first priority or when accessing the first file is interrupted with the second priority via the second mount point (Y). Computer system according to one of the preceding Claims 10 to 15 , characterized in that in the event of write access to the storage medium (1) by a first mount point (X), write access to the storage medium (1) is blocked by a second mount point (Y). Computer system according to one of the preceding Claims 10 to 16 , characterized in that in the case of write access to the storage medium (1), a different, second attachment point (Y) is removed by a first attachment point (X). Computer program, comprising instructions which cause the computer to execute the program, the method according to one of the Claims 1 to 9 perform. Computer-readable data medium on which the computer program according Claim 18 is saved.

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