JP2004054615A - Program for restoring equivalence of multiplexed external memory - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the throughput of all initializing processes to a minimum when starting a computer system, by performing the process of restoring the equivalence of an external memory concurrently with the other initializing processes in a well-balanced manner. <P>SOLUTION: A set copy value obtained by associating the amount of copies by each operation with copying intervals is stored and the contents of the external memory of a master system are copied onto the external memory of a slave system according to the set copy value. When copying of an entire area is complete, it is determined whether or not the other initializing processes are all complete; the set copy value is reset in such a way that when the other initializing processes are all complete, the process of restoring the equivalence of the external memory is preferentially performed to increase the amount of copies by each operation while shortening the copying intervals; when not all the other initializing processes are complete, the reverse is done. Thus, the throughput of all the initializing processes can be brought close to a minimum each time the computer system is started. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a resynchronization process for multiplexed external memories, and more particularly to a technique for improving the throughput of the entire computer system during the resynchronization process for multiplexed external memories.
[0002]
[Prior art]
In social systems, such as banking systems, in which computer system problems develop into social issues beyond just corporate activities or specific internal problems, the form of a load-sharing system using multiple computer systems is often used. Therefore, not only high processing capacity but also high reliability are strongly demanded. In such a social system, a plurality of computer systems share a large-capacity external memory that can be accessed at a high speed without issuing an I / O command for the purpose of constructing a hot standby system with higher speed and higher reliability. May be configured for use.
[0003]
The external memory has a high-speed data transfer capability, a large storage capacity (for example, 128 GB), a data protection function equivalent to that of the main memory, high reliability with a duplexing or quadrupling mechanism, a battery backup function, and the like. It is suitable for storage of a database, use of a paging area of a paging supervisor, a work area of a sort merge, a shared area between programs, and the like. The same data is stored in each of the multiplexed external memories, and this state is called equivalence of the external memories.
[0004]
When external memories are multiplexed, equivalence must always be guaranteed. If the equivalence is guaranteed, if any of the multiplexed external memories fails, the failed external memory is disconnected from the computer system and the operation continues using the remaining external memory. It becomes possible. If a hardware failure occurs in the external memory or the computer (CPU) during writing to the external memory, the equivalence of the external memory may be lost. In this case, the program that controls the external memory disconnects the failed external memory, but if the computer system stops before the external memory disconnection process is completed, the external memory remains lost in equivalence. It is possible that
[0005]
When the computer system starts up, the contents of the external memory (main system), which holds the correct contents as part of the initialization processing, are restored to the failed external memory (slave system) to restore the equivalence. This is called external memory equivalence restoration processing. However, when the computer system starts up, it is very difficult to determine whether a failure has occurred in the slave external memory and the equivalence has been lost.
[0006]
Various initializations, such as an IPL (Initial Program Loading) program, a nuclear initialization program, a master scheduler initialization program, and a subsystem startup program, are required to turn on the computer and use the computer system. The program group is executed. In a social system or the like that requires high reliability, the equivalence restoration program is executed each time the computer system is started up as one of the initialization programs in order to guarantee the equivalence of the external memory.
[0007]
In the resynchronization processing of the external memory, the CPU inquires whether the external memory was the main system or the sub system at the time of the previous operation via the CPU instruction to the external memory, and the contents of the main system external memory whose contents are guaranteed Is copied to a slave external memory. Since the external memory does not need to issue an I / O instruction unlike the case of accessing the external storage device, the data transfer speed is high, but the CPU is occupied during the resynchronization processing of the external memory, and other CPU processing is performed. There is a problem that parallel operation with is not possible.
[0008]
In order to solve this problem, when copying the contents of the main system external memory to the slave system external memory, the copying process is divided into a plurality of times and realized so as to operate in parallel with other initialization processes. As disclosed in "Method and Apparatus for Restoring Equivalence of Duplexed Shared Memory" in Japanese Unexamined Patent Publication No. Hei 8-202627, an external memory is divided into a plurality of areas, and a specific computer system is connected to another computer. An area to be copied is instructed to the system, and each computer system synchronously copies the allocated area of the external memory all at once.
[0009]
[Problems to be solved by the invention]
In a case where the restoration processing of the equivalence of the external memory is executed in parallel with other initialization processing at the time of starting the computer system, in order to minimize the start-up time of the computer system, the optimal one-time operation is performed for each computer system. It is necessary to set the copy amount per copy and the copy interval time. However, in order to estimate the optimal copying amount and copying interval time for each computer system, it is necessary to consider various factors such as the amount of resources of the computer system and system parameters, which is a very complicated and difficult task. It is.
[0010]
Japanese Patent Application Laid-Open No. 8-202627 discloses a "method and apparatus for restoring the equivalence of a duplicated shared memory". The system requires complicated program processing for simultaneously copying the areas of the external memory allocated synchronously. Also, since the restoration processing of the equivalence of the external memory and the other initialization processing are not controlled so as to operate in parallel, the processing time of the restoration processing of the external memory equivalence alone becomes faster, This does not minimize the throughput of the entire initialization process at the time of starting the computer system, including the process of restoring the equivalence of the external memory.
[0011]
In the future, it is expected that the number of operations for expanding all the files constituting the database to an external memory in order to further speed up the access to the database will be increased, and the size of the database will tend to increase year by year. Since the restoration processing time of the equivalence of the external memory becomes longer in proportion to the amount of the external memory, the time for the initialization processing at the time of starting the system is inevitably increased.
[0012]
The present invention has been proposed in view of the above-described circumstances, and the initialization process includes a LOAD process of a program from an external storage device, and expansion of information stored in the external storage device to a main memory. Of the I / O operation, the CPU restores the equivalence recovery processing of the external memory, which is mainly performed by the CPU instruction, and the other initialization processing in a well-balanced parallel operation, and sets the copy setting value every time the computer system is started. The goal is to minimize the overall system initialization throughput while automatically correcting.
[0013]
[Means for Solving the Problems]
FIG. 1 shows an overall configuration diagram of Embodiment 1 of the present invention. The multiplexed external memory equivalence restoration program 11 of the present invention uses the computer 1 based on a copy setting value 41 which associates a copy amount per copy with a copy interval time set by a system administrator. The contents of the external memory 0 (main system) 2 which was the main system at the time of the previous operation of the computer system are copied to the external memory 1 (sub system) 3, and the resynchronization processing of the multiplexed external memories is performed. is there.
[0014]
The equivalence restoration program 11 is positioned as one program of an initialization program group when the computer system is started, and stores a copy setting value in which a copy amount per copy is associated with a copy interval time, for example, a main memory. The setting value storage unit 111 stores the contents of the external memory 0 (main system) 2 to the external memory 1 (sub system) 3 based on the copy setting values using a CPU instruction. When the resynchronization processing is completed, the resynchronization processing is completed when the resynchronization processing is completed, for example, by referring to the completion message of the initialization program stored in the message log when the resynchronization processing is completed. If it is determined that another process group operating in parallel with the process has already been completed, the When it is determined that no is to function as a resetting means 113 for resetting the copy setting value so as to increase the execution priority of the other treatment groups are operated in parallel with the resynchronization process.
[0015]
In the present invention, in order to increase the execution priority of the equivalence restoration processing with respect to other processing groups operating in parallel with the equivalence restoration processing, the amount of one copy is increased, and the copy interval time is increased. This is realized by shortening or increasing the amount of one copy and shortening the copy interval time. Also, in order to increase the execution priority of another processing group operating in parallel with the equivalence restoration processing, the amount of copying at one time can be reduced, the copy interval time can be increased, or This is achieved by reducing the amount of copying each time and increasing the copying interval time.
[0016]
By configuring the present invention as described above, the initially set copy setting values are sequentially reset for the equivalence restoration processing at the time of starting the next computer system. Each time the computer is started up, the equivalence restoration processing centered on the CPU processing and the other initialization processing involving a large amount of I / O operations can be performed in parallel in a well-balanced manner. Throughput can be reduced to the shortest.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows an overall configuration diagram of Embodiment 1 of the present invention. In the computer 1 according to the present invention, when the power is turned on, an IPL program 12, a nuclear initialization program 13, an MS (master scheduler) initialization program 14, a subsystem activation program 15, etc. A series of initialization processing programs 10 is executed.
[0018]
The equivalence restoration program 11 is positioned as one program of the initialization program group 10 when the computer system is started up, and a copy setting value that associates a copy amount per copy and a copy interval time set by a system administrator. Based on the copy control table 51, the contents of the external memory 0 (main system) 2 are transferred to the external memory 1 (sub system) 3 based on the copy control table 51. Copying means 112 for copying using instructions;
When the resynchronization processing is completed, another processing group that is operating in parallel with the resynchronization processing when the resynchronization processing is completed is referred to by referring to the completion message of the initialization program stored in the message log. If it is determined that the copying has been completed, the copying amount per copy is increased, and the copying interval time is shortened. If it is determined that the copying has not been completed, the copying amount per copy is reduced, and It functions as resetting means 113 for resetting the copy set value 41 so as to lengthen the copy interval time, and is recorded on a computer-readable recording medium.
[0019]
The external memory 0 (main system) 2 is used as a storage area of a database, a paging area of a paging supervisor, a work area of sort merge, and the like. Further, the same data as the external memory 0 (main system) 2 is stored in the external memory 1 (sub system) 3 and the equivalence is maintained. Although the first embodiment is an example in which the external memory is duplicated, the present invention can be applied to a case where the external memory is multiplexed.
[0020]
The external storage device 4 includes a system parameter 42 used by the initialization program group 10, a program file 43 storing an operating system (OS) program and the like, and an external device used by the equivalence restoration program 11 set by the system administrator. A copy setting value 41 including a copy amount per one time and a copy interval time for controlling memory copy is stored.
[0021]
In the main memory 5 of the computer 1, the set value storage unit 111 of the equivalence restoration program 11 stores a copy set value 41 set by a system administrator as a copy control table 51.
FIG. 2 stores copy setting values used by the equivalence restoration program 11 for copy control of the external memory. The copy amount per copy is the copy amount per copy, such as 5 megabytes, when the contents of the external memory 0 (main system) 2 are copied into the external memory of the sub system in a plurality of times. In the time, an interval time, for example, one second, until the next copy processing is stored.
[0022]
FIG. 3 is a flowchart showing the flow of the resynchronization processing of the multiplexed external memory according to the first embodiment of the present invention. START1 is an entry of this processing, and START2 sets a timer value at a copy interval time specified by a copy setting value for the next copy processing divided into a plurality of times, enters a WAIT state, and restores equivalence by a timer interrupt. This is the entry when control is passed to the program.
[0023]
When the resynchronization program 11 is given control when the computer system is started, first, a copy set value including a copy amount and a copy interval time set by the system administrator is stored (S301). The contents of the external memory 0 (main system) 2 are copied to the external memory 1 (sub system) 3 using a CPU instruction according to the amount of copying per time (S302). When one copy is completed, it is determined whether or not the copy of the entire area of the external memory is completed based on the final address of each of the plurality of divided areas (S303).
[0024]
If the copying of the entire area has not been completed yet, use the watchdog timer interrupt function of the hardware and set the timer value to the copy interval time and START2 as the entry address to branch to when the watchdog timer interrupt occurs. Then, control is passed to another initialization program that has given the execution right to the equivalence restoration program (S304).
[0025]
When the copying of the entire area of the external memory is completed, it is determined whether or not the processing of another initialization program has already been completed (S305). When the computer system is started up, an OS is still being formed, so that the processing of the OS is assumed to be unusable. Therefore, even if each initialization processing program is executed serially and performs a parallel operation, it must be a pseudo-parallel operation using a function of hardware. Since the OS function cannot be used to determine whether or not other initialization processing has been completed, for example, whether or not a message indicating that the initialization program to be executed last has been completed has been output to the message log. to decide.
[0026]
As another implementation method, a flag is provided on the main memory 5 to the effect that the processing of the initialization program to be executed last is completed, and when the processing of the initialization program to be executed last is completed, this flag is turned on. The resynchronization program may be able to determine whether or not the processing of the last initialization program has been completed.
[0027]
If it is determined that the processing of the other initialization programs has been completed, the processing of the resynchronization program has not been completed by the completion of the other initialization processing. For example, if the set values of the copy amount and the copy interval time are 5 megabytes and 1 second, respectively, as shown in FIG. 2A, the copy amount per time is set to 10 as shown in FIG. By increasing the copy interval to 0.7 megabytes and shortening the copy interval time to 0.7 seconds, the copy set value is reset so that the ratio of executing the resynchronization program per unit time increases at the next startup of the computer system. Settings are made (S306).
[0028]
Since the resynchronization program performs a pseudo two-way parallel operation using any one of the other initialization programs and the watchdog timer interrupt, if the copy amount per one time set previously is increased, Since the execution time increases as the copy amount increases, the ratio of executing the equivalence restoration program per unit time increases, and the time for completing the processing decreases. Similarly, if the previously set copy interval time is reduced, the frequency at which the resynchronization program interrupts the execution of the processing of other initialization programs increases, so that the ratio of execution of the resynchronization program per unit time increases. The time to complete is shorter. It is assumed that the copy interval time is a sufficiently large value as compared with the time required for copying the external memory at one time.
[0029]
If it is determined that all the processes of the other initialization programs have not been completed, it means that the processes of the equivalence recovery program have been completed before the completion of the other initialization processes. If the set values of the copy amount and the copy interval time are 5 megabytes and 1 second, respectively, as shown by, the copy amount per time as shown by c in FIG. 2 to lower the execution priority of the equivalence restoration program Is reduced to 4 megabytes and the copy interval time is increased to 2 seconds, so that the next time the computer system is started up, the copy set value is reset so that the ratio of executing the resynchronization program per unit time is reduced. The setting is performed (S307).
[0030]
When the present invention is applied, once the system administrator only sets the copy setting value based on experience, every time the computer system is started, the copy setting value is reset toward the optimum copy setting value for the computer system. As a result, the throughput of the initialization processing including the equivalence restoration processing at the time of starting the computer system can be made closer to the minimum time.
[0031]
(Supplementary Note 1) A program for performing equivalence restoration processing of a multiplexed external memory by copying the content of a main external memory into a plurality of subordinate external memories in a plurality of times,
Setting value storage means for storing, in a storage device, a copy set value in which a copy amount per one time and a copy interval time are associated;
Copying means for copying the contents of the main system external memory to the slave system external memory based on the copy setting value;
When the resynchronization processing is completed, the resynchronization processing is completed when the processing of another processing group operating in parallel with the resynchronization processing is completed, and when the processing is not completed, the equivalence recovery processing is completed. An external memory equivalence recovery program for causing a computer to function as resetting means for resetting the copy setting value so as to increase the execution priority of another processing group operating in parallel with the sex recovery processing.
[0032]
(Supplementary Note 2) If the other processing group operating in parallel with the equivalence restoration processing has been completed at the time of completion of the equivalence restoration processing, the resetting means may determine the copy amount per time. 2. The resynchronization program for an external memory according to claim 1, wherein if it is large and not completed, the copy amount per one time is reset to a small value.
(Supplementary Note 3) The resetting means shortens the copy interval time if the other processing group operating in parallel with the equivalence restoration processing is completed at the completion of the equivalence restoration processing. The resynchronization processing program for an external memory according to Supplementary note 1 or 2, wherein the copying interval time is reset to be longer if the copying has not been performed.
[0033]
(Supplementary Note 4) A recording medium which records a program for performing equivalence restoration processing of a multiplexed external memory by copying contents of a main external memory into a subordinate external memory in a plurality of times. ,
Setting value storage means for storing, in a storage device, a copy set value in which a copy amount per one time and a copy interval time are associated;
Copying means for copying the contents of the main system external memory to the slave system external memory based on the copy setting value;
When the resynchronization processing is completed, the resynchronization processing is completed when the processing of another processing group operating in parallel with the resynchronization processing is completed, and when the processing is not completed, the equivalence recovery processing is completed. A computer readable recording a resynchronization program of an external memory that causes a computer to function as resetting means for resetting the copy setting value so as to raise the execution priority of another processing group operating in parallel with the resilience processing Recording medium.
[0034]
(Supplementary Note 5) An apparatus for performing a resynchronization process on a multiplexed external memory by copying the content of a main external memory into a subordinate external memory in a plurality of times,
Setting value storage means for storing, in a storage device, a copy set value in which a copy amount per one time and a copy interval time are associated;
Copying means for copying the contents of the main system external memory to the slave system external memory based on the copy setting value;
When the resynchronization processing is completed, the resynchronization processing is completed when the processing of another processing group operating in parallel with the resynchronization processing is completed, and when the processing is not completed, the equivalence recovery processing is completed. Resetting means for resetting the copy setting value so as to increase the execution priority of another process group operating in parallel with the sex recovery process.
(Supplementary Note 6) A method of performing equivalence restoration processing of a multiplexed external memory by copying the contents of a main external memory into a plurality of subordinate external memories in a plurality of times,
Storing in a storage device a copy setting value in which a copy amount per copy and a copy interval time are associated;
Copying the contents of the master external memory to the slave external memory based on the copy setting value;
When the resynchronization processing is completed, the resynchronization processing is completed if the processing of another processing group operating in parallel with the resynchronization processing is completed, and if the processing is not completed, the equivalence recovery processing is completed. Resetting the copy setting value so as to increase the execution priority of another process group operating in parallel with the sex recovery process.
[0035]
【The invention's effect】
The throughput of the entire computer system with the resynchronization processing of the multiplexed external memory and the other processing groups operating in parallel with the resynchronization processing of the external memory is increased every time the resynchronization processing of the external memory is performed. It becomes possible to approach the shortest time.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a first embodiment of the present invention; FIG. 2 is a copy control table according to the present invention; FIG. [Explanation of symbols]
1 Computer 2 External memory 0
3 External memory 1
Reference Signs List 4 external storage device 5 main memory 10 initialization program group 11 resynchronization program 12 IPL program 13 nuclear initialization program 14 MS initialization program 15 subsystem startup program 41 copy setting value 42 system parameter 43 program file 51 copy Control table 111 setting value storage means 112 copying means 113 resetting means

Claims (3)

A program for performing a resynchronization process of the multiplexed external memory by copying the contents of the main external memory into the subordinate external memory in a plurality of times,
Setting value storage means for storing, in a storage device, a copy setting value in which a copy amount per copy and a copy interval time are associated;
Copying means for copying the contents of the main system external memory to the slave system external memory based on the copy setting value;
When the resynchronization processing is completed, the resynchronization processing is completed if the processing of another processing group operating in parallel with the resynchronization processing is completed, and if the processing is not completed, the equivalence recovery processing is completed. An external memory equivalence recovery program for causing a computer to function as resetting means for resetting the copy setting value so as to increase the execution priority of another processing group operating in parallel with the sex recovery processing. The resetting means increases the amount of copy per one time when the other processing group operating in parallel with the equivalence recovery processing is completed at the time of completion of the equivalence recovery processing, and 2. The external memory equivalence restoration program according to claim 1, wherein if not, the copy amount per one time is reset to a small value. The resetting means shortens the copy interval time when another processing group operating in parallel with the equivalence recovery processing is completed when the equivalence recovery processing is completed, and 3. The resynchronization program for an external memory according to claim 1, wherein the copying interval time is reset long.

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