JPH0555902B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a high-speed swapping method in an information processing system implementing a virtual storage method using paging.

[Conventional technology]

Traditionally, the swapping method in information processing systems that implement a virtual memory method using paging consists of a page table, which is a table of page descriptors that holds the locations where pages exist, and a secondary memory for swapping that records each page. , a slot map that maintains the usage status of secondary storage for swapping on a record-by-record basis, a page table update means that updates the contents of a page table, a slot map update means that updates the contents of the slot map, a page table update means, and a slot map update means. and a channel program execution means for executing the channel program.

When a job swap-out request is input in such a swapping method, the channel program creation means requests the slot map update means to secure a number of records equal to the number of pages in the main memory that the job is using; The slot map update means refers to the slot map, secures empty records, and notifies the channel program creation means of the address of each record in the swapping secondary storage.

Furthermore, upon receiving the above notification, the channel program creation means transfers the contents of the main memory corresponding to each page descriptor of the page table to the address on the swapping secondary storage of each record notified by the slot map update means for each page. Create a channel program to execute the program and request the channel program execution means to execute it. Then, the channel program execution means executes the above channel program and transfers the contents of each page on the main memory to the swapping secondary memory.

Finally, the channel program creation means notifies the page table changing means of the address on the secondary storage for swapping of each record, and the page table changing means informs the page table changing means of the address on the secondary storage for swapping of the notified record. Change to address.

[Problem that the invention seeks to solve]

However, in the conventional swapping method, the usage status of the swapping secondary storage is maintained and updated on a record-by-record basis, so for example, when there are 30 consecutive empty records in the swapping secondary storage, the swapout of a certain job is Therefore, when 29 records are used, one isolated empty record may occur. As swapping is repeated, the addresses of free records on the swapping secondary storage become discontinuous,
Therefore, since the addresses of free records reserved for swap-out are also discontinuous, there is a drawback that the seek time and rotational wait time of the magnetic disk increase when a channel program is executed, and the swapping performance deteriorates. SUMMARY OF THE INVENTION An object of the present invention is to provide a high-speed swapping method that avoids such discontinuity in swapping areas and improves the above-mentioned drawbacks.

[Means for solving problems]

The high-speed swapping method of the present invention consists of a page table which is a table of page descriptors that holds the locations where pages exist, a secondary memory for swapping where records are recorded in units of pages, and a plurality of consecutive tracks as one unit. a unit map that maintains the usage status of the swapping secondary storage;
page table updating means for updating the contents of the page table so that the contents of the page descriptor become the first address of the unit of the swapping secondary storage; and a minimum number of units satisfying the number of pages specified by the swapping request. A channel program between the main memory and the swapping secondary memory is created using unit map updating means for updating the contents of the unit map so as to ensure the following: the page table updating means and the unit map updating means; It has a channel program creation means and a channel program execution means for executing the channel program.

〔Example〕

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, the high-speed swapping method consists of a main memory 10 that is divided into pages, a page table 20 that is a table of page descriptors 21 that holds the locations where pages exist, and a swapping memory that is made into records for each page. a unit map 40 that maintains the usage status of the secondary storage 30 for swapping on a unit-by-unit basis, a page table update means 50 that updates the contents of the page table 20, and a unit map update means 60 that updates the contents of the unit map 40. The page table update means 50 and the unit map update means 60 are used to update the main memory 10 and the swapping secondary memory 3.
a channel program creating means 70 for creating a channel program between
It consists of 0.

Next, the operation of the present invention will be explained.

One track of the swapping secondary memory 30 is 4.
It is assumed that the unit map 40 holds the usage status of the swapping secondary storage 30 with two tracks (eight records) as one unit.

At this time, if a swap-out request for job A is input as shown in FIG. The minimum number of units that satisfies "a certain number of pages" is calculated, and the unit map updating means 60 is requested to secure the number of units. The unit map updating means 60 then refers to the unit map 40 to secure empty units, and notifies the channel program creating means 70 of the address on the swapping secondary storage 30 of the first record of each unit.

Upon receiving the notification, the channel program creation means 70 converts the contents of the main memory 10 corresponding to each page descriptor 21 of the page table 20 into a swapping file for the first record of each unit notified by the unit map update means 60. Create a channel program to transfer to the next storage address. At this time, as shown in FIG. 3a, the addresses on the swapping secondary storage 30 are consecutive for records in the same unit, so
Seeking and waiting for rotation are unnecessary. In addition, Fig. 3b
shows an example of the program configuration of the conventional swapping method.

Next, the channel program creation means 70 requests the channel program execution means 80 to execute the channel program, and the channel program execution means 80 executes the channel program to swap the contents of each page on the main memory 10. Transfer to secondary storage 30.

Finally, the channel program creating means 70 notifies the page table changing means 50 of the address on the swapping secondary storage of the first record of each unit. The page table changing means 50 transfers the contents of the page descriptor 21 to the address on the swapping secondary storage of the notified first record of the unit if the transferred record is the first record of the unit; Change the address to a contiguous address.

FIG. 4 shows the state after the channel program is executed.

In this way, the seek time and rotational waiting time of the magnetic disk are reduced, making high-speed swapping possible.

〔Effect of the invention〕

As described above, according to the high-speed swapping method of the present invention, the seek time and rotation waiting time of the magnetic disk are reduced, so that a high-speed swapping operation can be realized.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, and FIG.
The figure is an explanatory diagram showing the case where a swapping request for job A is input (before processing). Figure 3 is an explanatory diagram showing a channel program that is created and executed when a swapping request for job A is input.
The figure is an explanatory diagram showing a case where a swapping request for job A is input (after processing). 10...Main memory, 20...Page table, 2
1...Page descriptor, 30...Secondary storage for swapping, 40...Unit map, 50...Page table update means, 60...Unit map update means, 70...Channel program creation means,
80...Channel program execution means.

Claims (1)

[Claims] 1. In an information processing system that implements a virtual storage method using paging, there is a page table which is a table of page descriptors that holds the location where a page exists, and a secondary swapping table that is a record for each page. a unit map for retaining the usage status of the swapping secondary storage with a plurality of continuous tracks as one unit; and a unit map configured to set the contents of the page descriptor as the start address of the unit of the swapping secondary storage. page table updating means for updating the contents of the page table; unit map updating means for updating the contents of the unit map so as to ensure a minimum number of units satisfying the number of pages specified by the swapping request; and the page table updating means. The apparatus is characterized by comprising a channel program creating means for creating a channel program between the main memory and the swapping secondary memory using the unit map updating means, and a channel program executing means for executing the channel program. High-speed swapping method.