JPS6055451A - Estimating device for data base performance - Google Patents

Abstract

PURPOSE:To estimate automatically the performance of a data base and to lighten the load on a designer by modeling the data base access part of a base control system, and simulating it. CONSTITUTION:A control part 1 for the estimation of data base performance receives an input from an access bus 6 to integrate a basic access processing time, and outputs the performance result. The processing time is estimated by a basic access time processing part 2 at intervals of basic access. A currency indicator simulator part 3 simulates the state of a currency indicator at a request from the basic access time processing part 2. A disk input/output time estimation part 4 estimates the time of input to and output from a disk. A buffer simulation part 5 simulates the state of a buffer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a database performance estimating device, and more particularly to a database performance estimating device that is used before actually constructing a database or when changing the structure of a database.

Traditionally, when designing a database, we first analyze requests from database users, create a data structure, and then create a data structure for the database management system using the data definition language provided by the database management system. register. At this time, the database designer needs to consider the size of the database and the access frequency, and at the same time, optimize the data structure so as to satisfy the data retrieval and data sand tray requests from database users. Furthermore, in order to estimate the time required for the processing desired by the user, the database designer needs knowledge about the performance of the database management system.

This has the disadvantage that a database designer requires considerable skill and extensive experience.

The purpose of the present invention is to eliminate the drawbacks associated with conventional database design, and to automatically estimate the performance of database design, that is, data structure, for database designers, thereby lightening the burden on designers in database design. The purpose of this invention is to provide a database performance estimation device that can perform the following.

According to the present invention, there is provided a basic access time estimator that inputs an access bus description command corresponding to the function of a data manipulation language of a database management system and l to l, and estimates the time required for basic access according to the command. , database performance estimation that issues a request signal to the basic access time estimator, integrates the estimated time as a response from the estimator every time the command is input, and outputs the integration result upon input of an estimation end command. A control unit and a request from the basic access time estimating unit estimate the processing time required for input/output to the disk device.A request from the disk output processing time estimation unit and the basic access time estimating unit,
A buffer simulator section that simulates buffer management that manages the input/output of data in the 0 work area to and from the disk device in the database management system, and manages the current indicators set for each record type and set type in the database structure. A database performance estimating device is obtained, which is characterized by comprising a currency indicator simulator section that simulates currency management.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the present invention. In FIG. 1, this embodiment shows a file that describes access to a database, an access bus 6, and a database performance estimation that inputs the access bus 6, integrates the basic access processing time, and outputs the performance result. a control unit 1, a basic access time processing unit 2 that estimates processing time for each basic access, and a currency indicator simulator unit 3 that simulates the state of the currency indicator according to a request from the basic access time processing unit 2. , a disk input/output time estimation unit 4 that estimates input/output time to the disk, and a buffer simulator unit 5 that simulates the state of the buffer.

Table 1 describes examples of basic accesses for each database operation language DML provided by the database management system and for each command of the language.

Table 1: In the database performance estimation control unit l, the commands shown in Table 1,
For example, FIND(1) to FIND(7), GET.

After interpreting MODIFY... etc. using access path 6, basic access command 1 as shown in Table 1 is executed.
IND-DB FIND-CALCFIND-USIN
G... Execute GET, MODIFY, etc. and notify the basic access time processing unit.

Table 2 shows a part of the processing contents of the basic access time processing unit 2. Basic access FIND-DB requested from the database performance estimation control unit 1.

FIND-ANY, F'IND-FIR8T (Indicates that each process shown in Table 2 (a) is executed for each D condition. Table 2 (b) is related to Table 2 (a) This is an explanation of terms.

lbJ 181 table related information! O Explanation No. zp Basic Access Processing Unit (Part) FIG. 2 is a flowchart showing the internal processing of the KARE/CE/JIKE simulator unit 3. In Figure 2,
The currency indicator uses a database management system of the so-called C0DASYL type (Note 1) CODASYL type D.
For BMS, C0DASYLData Desc
viption Language Journal o
f Development-1opment1978, The
5ecvetarian of the Canada
a Government EOP Standard
This is a state that is set for each record or set when referring to dsCommittee (197B).

In the currency indicator Zomierator, conAs
For yL type, the current position is the owner for each set.

It has a state of being in first, first, or other states.

FIGS. 3(a) and 3(b) are flowcharts showing the internal processing of the Nokutsufashimikureta which simulates the management of buffers in a database management system. In FIG. 3, the content of buffer management differs depending on the database management system, but in the case of the C0DABYL type, it is usually managed for each area, which is a subset of all record types. Therefore, as shown in the flowchart example showing the internal processing of the buffer management simulator 4, requests from the basic access time processing unit 2 include an area number that uniquely identifies an area, a record type number that uniquely identifies a record type, and a request for buffer management. This is a command to register, modify, check, or delete.

Figure 4 (a) Φ) F! , , is a flowchart of the internal processing of the disk input/output time estimating unit 4 that returns to the basic access time processing unit 2 the processing time required for one input/output process to the disk device in which the database is stored.

In FIGS. 4(a) and 4(b), when the basic access time processing unit 2 is given the disk device type number and disk access format page size, the basic access time processing unit 2 determines the disk device input/output processing time by referring to the table. It is returned to the time processing unit 2.

The flowcharts shown in FIGS. 2 to 4 and Table 2 are only one embodiment, and other embodiments can be easily derived from this embodiment as long as the functions in each block in FIG. 1 are satisfied. Can be done. t7'c The content of this embodiment is changed depending on the internal processing logic adopted by the target database management system. It is obvious from one thing.

However, the purpose of the present invention is to estimate the performance of data structures,
Therefore, since a feature of the present invention is that it internally has the configuration shown in FIG. 1, it is clear that the configuration shown in FIG. 1 is included within the scope of the claims of the present invention. Further, in the present invention, even if the processing parts shown in FIG. 1 have different names, as long as their functions are the same, it is clear that there is no difference in the processing parts.

Now, embodiments of the invention will be further described using FIGS. 2, 3, 4, and Tables 1 and 2. For convenience of explanation, the access bus is FIND, which searches the database.
Assume that there is only one instruction.

Let's take up the model FINDANY. This access bus is input to the database performance estimation control unit l as shown in Figure 1, and is changed to the FIND-CALC command, which is a basic access, as shown in Table 1, and basic access time processing 2 control is transferred. . Here, FIND-C
In accordance with the ALC command, the number of inputs and outputs to the disk is calculated using the formula shown in Table 2. At this time, as shown in Table 2, there is a basic access to calculate the output contents of the buffer adjuster 5 and the currency indicator simulator 6. After this, using the number of input/outputs and the one-time input/output processing time from the disk input/output time estimator, FIND-C
The processing time required for ALC processing is accumulated, and control is returned to the original database performance estimation control unit l. This control unit 1 adds the output of the basic access time processing 2 in order to calculate the total processing time in the case of an access consisting of multiple instructions, and outputs the estimated processing time after the instruction ends.

As explained above, the present invention attempts to model the database access part of a database management system, simulate it, and estimate the performance of the database. By intuitively or by actually constructing a database for evaluation, it is possible to largely automate the process of estimating database performance, thereby significantly reducing the burden on those involved in Proposition 1.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a flowchart of internal processing of the currency indicator simulator section in this embodiment, and FIGS.
) is a flowchart of the internal processing of the buffer adjuster that simulates the management of buffers in the database management system in this embodiment, and FIGS. 4(a) and 4(b) are diagrams showing the disk input/output time estimation unit in this embodiment FIG. 2 is a diagram showing a flowchart of internal processing. l...Database performance estimation control unit, 2...
. . . Basic access time processing section, 3 . . . Currency indicator simulator section, 4 . . . Disk input/output time estimation section, 5 . . . Buffer simulator section, 6...Half 1 old trench 2 moss 3 pieces

Claims (1)

[Claims] Functions and functions of data manipulation languages in database management systems
a basic access time estimator that inputs an access path description command corresponding to pair l and estimates the time required for basic access according to the command; and an estimator that issues a request signal to the basic access time estimator. A database performance estimation control unit that integrates the estimated time that is a response from the above command every time the command is input and outputs the integration result when the estimation end command is input, and a database performance estimation control unit that integrates the estimated time as a response from A disk input/output processing time estimator that estimates the processing time required for input/output, and a buffer that manages input/output of data in a work area to and from a disk device in the database management system based on requests from the basic access time estimator. A database comprising a buffer simulator section that simulates management, and a currency indicator simulator section that simulates currency management that manages currency indicators set for each record type and set type in the database structure. Performance estimation device.