JPS6345657A - Virtual memory control system for virtual computer system - Google Patents

Abstract

PURPOSE:To secure same executing performance as a real computer for a virtual computer system by sharing a virtual memory control function with plural operating systems. CONSTITUTION:The address spaces of a real memory control means 51 and a real memory control table 52 produced by an operating system 2 are set equal to the address spaces of the means 51 and the table 52 produced by an operating system 3. Thus both systems 2 and 3 can share a virtual memory control part 5. Therefore the part 5 inputs a virtual address 20 of the system 2 or a virtual address 30 of the system 3 to execute the address conversion. Thus it is possible to obtain a real address in a real memory just with the dynamic conversion of virtual addresses of a single step.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a virtual storage control method in a virtual computer system.

[Conventional technology]

A virtual memory control method in a conventional virtual computer system will be explained based on FIG. 3. The virtual address (301) of virtual computer c (hereinafter referred to as guest) is converted using a guest conversion table stored in the main memory of the guest (■).

After applying the guest's prefix conversion, we obtain the guest's absolute main memory address (302i. This address is L1
Verify that it is within the tolerance range indicated by ``N''
The offset indicated by ``?In addition, it is converted to the virtual address (303) of the actual computer C and below (hereinafter referred to as host).As shown by ■, the virtual address of the host is = the absolute address of the host using the host conversion table. (304).The above is 1 Nikkei Electronics 198
4.4.23 (Floor 341) Pages 207-233 "System/370 Extended Architecture Virtual Machine".

[Problem that the invention seeks to solve]

The virtual memory control method in the conventional virtual computer system described above first performs virtual address conversion using the virtual memory management function of the operating system of the virtual machine, and then converts the virtual address again using the virtual memory management function of the operating system for the virtual computer system. Since conversion has to be performed, that is, two-step address conversion has to be performed, execution performance has been degraded.

[Means for solving problems]

The virtual memory control method in a virtual computer system according to the present invention is a virtual memory control method for a virtual computer system in which a plurality of computer systems having a virtual memory management function are operated on one real computer system running the same type of operating system. In memory control methods.

a sharing means for placing and sharing the virtual memory management functions of the operating systems of the plurality of computer systems in a system shared address space using a segmentation method; Dynamic address translation means for converting addresses into real addresses.

real memory management means for centrally managing the real addresses of the real memory obtained by the dynamic address conversion means based on a real memory management table, and real memory management means that centrally manages the real addresses of the real memory obtained by the dynamic address conversion means based on the real memory management table; The feature is that a real address can be obtained.

〔Example〕

Next, the present invention will be explained in detail using one drawing.

Referring to FIG. 1, which shows one embodiment of the invention.

The virtual computer system 1 of this embodiment includes a real memory 6 and virtual computers A and Bi. Virtual machines A and B are operating systems 2 and 3 respectively? include. A virtual memory management function sharing means 4, a virtual memory management unit 5 consisting of a dynamic address conversion means, a real memory management means 51, and a real memory management table 52 are shared by the virtual machines A and B.

In this embodiment, there are only two virtual machines, that is, operating systems that operate on the virtual machine system, but there may be two or more.

In this embodiment, the virtual memory management function sharing means 4 controls the virtual memory management unit 5 from the operating systems 2 and 3.
is located on the system shared address space of operating systems 2 and 3 using a segmentation method so that it can be shared on virtual machine system 1.

That is, the address space of the real memory management means 51 and real memory management table 520 created by the operating system 2 is the same as the address space of the real memory management means 51 and the real memory management table 52 created by the operating system 3. As a result, the virtual memory management unit 5 can be shared by the operating systems 2 and 3.

As a result, the virtual memory management unit 5 adds the virtual address of the operating system 2 or adds the virtual address 31 of the operating system 3 and performs address conversion.

Between the dynamic address translation means, the virtual address 20 of the operating system 2 is input, and the segmentation
Address translation is performed using the paging method. As a result of address conversion, if it exists in the real memory 6, the real address 60 is accessed directly. If it does not exist in the real memory 6, the real memory management means 51 is notified of this fact.

The real memory management means 51 stores real memory 6 for each byte page in 4
An unused real page is allocated based on the real memory management table 52 that manages the use/unuse of real addresses, and data etc. specified by the virtual address are loaded therefrom from the secondary storage device. The allocated real page of the real storage management table 52 becomes in the "used" state. If there are no unused real pages.

After searching for the least recently used real page among the real pages in the "used" state and ejecting that real page from the real memory 6 to the secondary storage device.

The actual page is set as an unused page, and the operation for the unused page described above is performed. Thereafter, the above dynamic address translation means (material) is again used.

Next, with reference to FIG. 2, the detailed operation of the virtual memory management function sharing means 4, which is the sharing means of the virtual memory management unit 5 located on the system shared address space, will be explained.

Processes A and B of virtual machine A operate using the virtual memory management unit 5 of segment S-1, which is a system shared segment. For this purpose, segment S-1 is linked to segment table 5T-11 from the second entry in segment table display word string 5TWA-A, which is linked by process A, and is further linked to segment table 5T-11.
8(2) Linked from the nth entry. The nth entry in the segment table 5T-3 defines the attribute of the segment as a system shared segment. Similarly for process B.

k of segment table display word string 5TWA-B linked by process B (segment table display word string 5TWA-
Segment table 5T-8 is linked from IJ.

Processes X and Y of virtual machine B are also linked by process X so that they can use the same virtual memory management unit 5 as processes A and B of virtual machine A, that is, so that they can access segment S-1'i. k of segment table display word string 5TWA-X (segment table display word string S
The segment table 5T-8 is linked from the 1-th entry of TWA-A. Similarly, for process Y, 5T-8 is linked from the kth entry (same value as k in segment table display word string 5TWA-A) of segment table display word string 5TWA-y linked by process Y. ing.

Note that segments A-1, B-1, X-1, and Y-1 are unique segments of processes A, B, X, and Y, respectively, and segments AB-1 and
and B, the shared segment of processes X and Y.

〔Effect of the invention〕

As explained above, according to the present invention, by sharing the virtual memory management function among multiple operating systems, a real address can be obtained through one-step dynamic address conversion. Even in this case, the execution performance is the same as when running on a real computer system.

[Brief Description of the Drawings] Fig. 1 is a block diagram of an embodiment of the present invention, 1st...virtual computer system, 2, 3... operating system, 4... shared virtual memory management function. Means, 5...
Virtual memory management unit, 6... Real memory, 20.30...
Virtual address, 50...Dynamic address translation means, 51
. . . Real memory management means, 52 . . . Real storage management table, 60
...Real address. Iku U edition 11L my system figure 3

Claims (1)

[Claims] 1. Among computer systems with virtual memory management functions,
In a virtual memory control method for a virtual computer system in which a plurality of computer systems running the same type of operating system are operated on one real computer system, the virtual memory management function of the operating systems of the plurality of computer systems is controlled by a segmentation method. a shared means placed in a system shared address space for shared use; a dynamic address conversion means for converting a virtual address of each of the operating systems into a real address using the shared virtual memory management function; and the dynamic address conversion means. and a real memory management means for centrally managing the real addresses of the real memory obtained by the method based on the real memory management table, and the real address of the real memory can be obtained by only one step of dynamic address conversion of the virtual address. A virtual memory control method in a virtual computer system characterized by.