JPS6231386B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a digital computer system with an improved startup method.

An electronic computer system (hereinafter simply referred to as a computer) with an external storage device (hereinafter referred to as bulk) stores an operating system (hereinafter referred to as OS) in the bulk, and at startup, the OS in the bulk is transferred to the main memory. Normally, operations are started by transferring the OS instructions to the CPU and starting to execute them one after another at startup. FIG. 1 is a computer configuration diagram showing a startup method for one of the most common CPUs (central processing units). In the figure, 1 is the main memory, 2 is the CPU,
3 is a bulk, and the CPU 2 can access the main memory 1 and the bulk 3 via a bus 4. In addition, 5 is an initial loader (hereinafter referred to as IL) for loading the program, and this
When the IL ₅ receives the activation signal 6, it causes the CPU ₂ to start activation. That is, when the IL ₅ transmits the activation signal 6 to the CPU ₂ , the CPU writes a group of instructions in the memory 7 in the IL to the memory 1, and further, the CPU executes the instruction group written to the memory 1 in order. In this way
CPU operation starts. Here, when CPU ₂ executes the instructions in memory 7, the instructions in bulk 3 are
It is usually configured to transfer OS ₈ to main memory 1 and then branch to the OS entry instruction. In this way, the OS starts. FIG. 2 shows a combination of a plurality of computers explained using FIG. 1.

The method of starting the CPU _2a is almost the same as that of the CPU ₂ in FIG. That is, the instruction group in the memory 7a is structured as shown in the flowchart of FIG.

To explain the flowchart of FIG. 3, in the first step SteP _1, the bulk 3a is transferred to the main memory 1, and as a result, it is determined in the second step SteP ₂ whether or not the transfer was successful. If successful, the process moves to the third step, Step ₃ , and branches to the OS entrance of the main memory 1a. If it fails, the process moves to the fourth step, Step ₄ , and the OS is transferred from the bulk 4c to the main memory 1a. When this is completed, the process moves to the fifth step, Step ₅ , where it is determined whether the transfer is successful or not, and if it is successful, it branches to the OS, and if it is not successful, it ends. Here, either OS ₈ a or OS ₈ c is transferred, so even if bulk 3c is out of order, bulk 3
If c is normal, the CPU 2a can transfer and operate the OS. Note that the memory 7b also stores a group of instructions with the same concept as the memory 7a, and if either bulk 3b or 3c is normal, the CPU _2b
The OS can be transferred and operated. It has been conventionally practiced to increase the reliability of the system by combining a plurality of CPUs and a plurality of bulks in this way.

For example, when bulks 3a and 3b in Fig. 3 are stopped, both CPU ₂ a and CPU ₂ b are connected to bulk 3c.
It will run on OS _8c , bulk 3a,
It can operate even if 3b is stopped.

However, depending on the OS, when the CPU _2a executes the OS in the main memory 1a, data is transferred to the OS ₈ in the bulk 3c, so that both CPUs may not operate properly.

For example, if OS _8c has only one rollout area for temporarily saving programs running in main memory 1a, both CPUs
Even if it starts working with OS _8c , both CPUs will eventually become unable to work.

To prevent this, it is necessary to ensure that CPU ₂ a and CPU ₂ b do not operate at the same time while bulks 3 a and 3 b are stopped; however, if they are started by mistake, bulk There was a risk that the contents of 3c would be destroyed.

The present invention has been made in view of the above circumstances, and it transfers one operating system from among a plurality of operating systems stored in an external storage device to main memory, and sequentially executes instructions of that operating system. In a system consisting of multiple central processing units that operate by executing on a central processing unit (CPU) and a shared external storage device that can be accessed by these multiple central processing units and stores multiple operating systems. , a storage device accessible from each central processing unit is provided for registering the use of the operating system used by each central processing unit among the respective operating systems, and each central processing unit uses the new operating system. At that time, it is determined from the registered contents whether the operating system to be used is being used by another central processing unit, and if it is not being used, the use of the operating system is registered, and each central processing unit When each central processing unit starts up, it determines which operating system the central processing unit is running on. An object of the present invention is to provide an electronic computer system that can operate its central processing unit using an operating system, and that can prevent destruction of memory contents in bulk due to repeated use of the same operating system. .

4 to 7 regarding one embodiment of the present invention.
This will be explained with reference to the figures. FIG. 4 is a configuration diagram of a computer using the startup method according to the present invention.
The memory 1c that can be accessed from CPU ₂ a and CPU ₂ b via buses 4 a and 4 b, respectively, is connected, and the instruction groups of memories 7 a and 7 b of IL ₅ a and IL ₅ b are shown in FIGS. 5 and 7, respectively. It is the same as FIG. 2 except that it is as shown. The memory 1c is the fifth memory 1c.
It is configured as shown in the figure, and the OS transfer bulk name of CPU ₂ a is stored in memory 10, the OS transfer bulk name of CPU ₂ b is stored in memory 11, and the operation flag of CPU ₂ a is stored in memory 1.
2, the operation flags of the CPU _2b are respectively stored in the memory 13.

In the above configuration, the operation when starting the CPU ₂ a while the bulks 3 a and 3 b are out of order and then trying to start the CPU ₂ b will be explained.

When the activation signal 6a is input to the IL _5a , the CPU _2a writes the contents of the memory 7a to the main memory 1a and sequentially executes the instructions. Since the contents of the memory 7a are configured as shown in FIG. 6, processing A, determination B,
It is stored that Process E, Judgment F, Judgment G, Process H, and Process I were executed in this order, and that OS _8c was transferred and activated from the bulk 3c. That is, in the first step, Process A, the OS is transferred from the bulk 3a to the main memory 1a.
is transferred, and in the second step, determination B, it is determined whether the transfer is successful or not based on the bulk 3a. If successful, move on to the third step, Process C.
Here, the transfer bulk name "3a" is written into the memory 1c. The process then enters the fourth step, process D, and branches to the OS entrance of the main memory 1a. If judgment B is unsuccessful, the fifth step, processing E, is entered, and the bulk 3c is transferred to the main memory 1a.
Transfer the OS. Then, in the sixth step, a routine F for determining the success or failure of transfer from the bulk 3c is entered, and if the transfer is successful, the next determination routine, determination G, is executed. Here, it is determined whether another CPU has transferred the OS from bulk 3c, and if not, it executes process H to write the transfer bulk name "3c" to main memory 1c, and enters the next process I. Branches to the OS entrance of memory 1a. If F is negative, and G is positive, the process ends. or
The CPU _2a writes a value to increase the value in the memory 12 in constant synchronization.

In this state, when starting signal 6b is input to IL ₅ b,
The CPU _2a writes the contents of the memory 7b to the main memory 2a and sequentially executes the instructions. Since the contents of the memory 7b are configured as shown in FIG. 7, which is basically the same as the flowchart shown in FIG. 6, processing A, judgment B, processing E, judgment F, and judgment G are executed in this order.
Do not branch to OS.

Here, determination G will be explained in detail. Judgment G
This is performed by referring to the memory 1c that can be accessed by each of the CPUs _2a and _2b . There are other things in memory 1c.
Since the CPU remembers the bulk name to which the OS was transferred, CPU ₂ a determines the bulk name used by CPU ₂ b from memory 11, and CPU ₂ b determines the bulk name used by CPU ₂ a from memory 10. do.

Furthermore, the memory 12 and the memory 13 are each
Since CPU ₂ a and CPU ₂ b count up only when they are operating, CPU ₂ a determines whether CPU ₂ b is operating by referring to memory 13.
CPU ₂ b refers to memory 12
Determine whether CPU _2a is running. In this way, CPU ₂ a refers to memory 11 and determines that CPU ₂ b has transferred the OS from bulk 3 c, and also refers to memory 13 and determines that CPU ₂ b is in operation since the count has been increased. If it is determined that there is
Branch decision G to YES and do not branch to OS. In other cases, the decision G branches to NO and finally branches to the OS.

In this way, CPU ₂ b stops immediately after starting, and as a result is not started. For these reasons, the CPU _2b does not write to the OS _8c of the bulk 3c, so the bulk 3c will not be destroyed. Although the explanation so far has been given for the case of two CPUs and three bulks, it is similarly possible to implement any number of CPUs and bulks.
Also, in Figure 4, only bulk 3c is CPU ₂ a,
Although this is an example of a configuration that can be accessed from the CPU ₂ b, it can be similarly realized in a case where both the bulks 3 a and 3 b can be accessed from the CPUs ₂ a and ₂ b. In addition, in Figure 4, we have explained the case where the bulk used by other CPUs is determined by the memory 1c in CPUs _2a and _2b , but there are other methods that do not change the main idea, such as methods using process input/output devices and data transmission. There are various possibilities, but any method can be used to determine whether the OS is being used by another CPU.

As described in detail above, the present invention transfers one operating system among a plurality of operating systems stored in an external storage device to the main memory, and sequentially executes the instructions of the operating system to the central processing unit (CPU). ), and a shared external storage that is accessible by the plurality of central processing units and stores a plurality of operating systems. A storage device accessible from each of the central processing units is provided for registering the use of the operating system used by each of the central processing units, and each central processing unit uses the storage device when using a new operating system. It is determined from the registered contents whether the operating system is being used by another central processing unit, and if the operating system is not being used, the use of the operating system is registered. When the central processing unit starts up, the central processing unit runs using an operating system that is not currently being used by any of the multiple operating systems that are already running. In a system that operates with a central processing unit as a component, it is possible to avoid redundant use of operating systems being used by other central processing units, improve reliability, and store multiple operating systems. Therefore, it is possible to provide an electronic computer system that can prevent serious situations such as bulk content destruction in some cases if it is started up by mistake.

[Brief explanation of the drawing]

1 and 2 are diagrams showing an example of the configuration of a computer system, FIG. 3 is a flowchart showing the execution procedure at the start of the system, and FIG. 4 is a block diagram showing an embodiment of the present invention. , Figure 5 shows its usage.
Diagrams showing memory contents for OS registration, Figures 6 and 7
The figure is a flowchart showing the execution procedure at the time of start in the system of the present invention. 1a, 1b...main memory, 1c...memory, 2a,
2b...Central processing unit (CPU), 3a, 3b, 3c
... Bulk, 4a, 4b... Bus, 5a, 5b... Initial program loader.

Claims (1)

[Claims] 1. It operates by transferring one operating system among multiple operating systems stored in an external storage device to the main memory and sequentially executing the instructions of this operating system by the corresponding central processing unit. In a system consisting of a plurality of central processing units and a shared external storage device that is accessible by the plurality of central processing units and stores a plurality of operating systems, the main memory of each central processing unit of each operating system is A storage device is provided that can be accessed from each central processing unit to register the use of the operating system used by each central processing unit, and each central processing unit registers whether or not the new operating system will be used for other purposes. an electronic computer, characterized in that it has a function of determining the operating system based on the registered contents of the storage device, and enabling the use of the operating system after registering the use of the operating system when the operating system is not being used. system.