JPS63237141A - Segmented data set updating system - Google Patents

Abstract

PURPOSE:To effectively utilize an unnecessary data region by writing the number of tracks which members use in a directory part and arranging it in the lowest rank of an extent when at least one track unit is vacant. CONSTITUTION:A pointer TTR which shows the storing destination of members A, B... in a member part 2-2 is provided in the directory part 2-1 of the partitioned data set 2 of a file 1 and a directory updating part 5, a data ineffective process part 6 and VTOC (Volume.Table.Of.Contents) updating part 7, etc., are provided in a processor 4. And during a data updating process of the updating part 5, the process part 6 detects that at least one track unit is vacant so as to arrange the vacant track in the lowest rank of the extent of the VTOC at the time of detecting it and a directory, etc., transmission part 8 relocates the updated VTOC 3 and the directory in the file 1.

Description

[Detailed description of the invention] [Table of contents] Overview Industrial field of application Prior art (Figure 5) Problems to be solved by the invention Means for solving the problems (Figure 1) Working examples (Figure 1) (Figures 2 to 4) Effects of the invention [Summary] A space management method for a partitioned data set that makes each track reusable by setting the track that is no longer in use as the last extent of the data set. It is.

[Industrial application field]

The present invention relates to a partitioned data set update method, and particularly to a method that allows efficient use of unnecessary data areas generated when updating and deleting members.

[Conventional technology]

Partitioned data sets are widely used because they can have multiple members within one data set, and have the advantage of being able to collectively manage data with similar purposes.

For example, as shown in FIG. 5, the segmented data set includes a member section in which members A, B, and C- are stored, and a member section in which members A, B, and C- are stored;
It is provided with a directory section that indicates the storage address of B, C-. The existence range of this partitioned data set is V T OC (Volume Table Of Co
contents).

A directory section is provided at the beginning of the partitioned dataset,
A pointer TTR indicating the storage location of the data of members A, B, C-, etc. of the segmented data set is written.

[Problem that the invention seeks to solve]

In such a partitioned data set, for example, member B
When updating data, conventionally, the area previously used by member B is invalidated, and member B's updated data is written at the beginning of the free area of this partitioned data set.
The pointer of member B in the directory section is replaced with this update data writing light.

Therefore, each time data of a member is updated or deleted, the previously used area becomes an unnecessary data area, resulting in a problem that the usage efficiency of the storage device deteriorates.

An object of the present invention is to provide a partitioned data set update method that prevents deterioration in the utilization efficiency of a storage device due to unnecessary data areas that occur when updating and deleting members.

[Means for solving problems]

In order to achieve the above object, in the present invention, as shown in FIG.
-.- has a pointer TTR indicating the storage location in the member section 2-2, and in the processor 4, the member AS
When updating (or deleting) one of B. In 2-2, the invalidation process for the member is performed, and by sorting all pointers in the directory section into TTR[, the number of tracks freed by deletion of the member is calculated. Further, the pointer TTR of the member after the track to be released is corrected by the number of tracks.

VTOC update unit update 7Update VTOC3.

When updating this VTOC3, the track calculated by the data invalidation processing unit is registered in the lowest extent in VTOCa. The VTOC 3 and directory updated in this manner are relocated into the file 1 by the directory etc. sending unit 8.

[Effect]

Since the updated or deleted track is registered on the VTOC as the final extent of the segmented data set, by sequentially performing this process, the track can be sequentially reused.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS. 2 to 4.

FIG. 2 is a configuration diagram of an embodiment of the present invention, FIG. 3 is an explanatory diagram of the operation of the present invention, and FIG. 4 is an explanatory diagram of the state of VTOC and partitioned data sets in the present invention.

In the figure, parts with the same reference numerals as those on the map indicate the same parts, and 8' is a transmitting/receiving unit which performs read/write control of data to file 1 and includes the directory etc. sending unit 8 in FIG. 1. .

9 is a memory, and 10 is a 17211 section which comprehensively controls the directory update section 5, data invalidation processing section 6, VTOC update section 7, transmission/reception section 8', and memory 9.

The operation of the present invention will be described, for example, in the case of deletion of member B, with reference to the operation flowcharts 380(A) and 380(B) and the file state explanatory diagram.

■ Sending/receiving 8' is from file 1 to its directory section 2-
1, and read out all members of 1, and store the pointer TT.
Sort R and hold it in memory 9. Then, the directory section 5 deletes the member B section of the directories 2 to 1 of the file 1, and performs an update process.

(2) Next, the data invalidation processing section 6 deletes member B of the member section 2-2. At this time, it is determined from the TTRs of all members held in the memory 9 whether a track becomes vacant due to the deletion of member B.

■ If there is an empty space of one track or more, the VTO
The C update unit 7 updates the VTOC3 in the file 1.

At this time, empty track Y generated due to deletion of member B
is written at the bottom of the extent. (then VTOC
3 is changed as shown below in Figure 3 CB).

(2) Due to this deletion of member B, the directory update section 5 updates the addresses TTR of other members after member B in the directory section 2-1. In this way, empty tracks can be effectively utilized in member processing of partitioned datasets.

The update status of the VTOC in sections (1) to (2) above will be explained in detail with reference to FIG. When the member section in file 1 is used in the state shown in FIG. 5, for example, in the present invention, the VTOC is in the state shown in FIG. 4(A).

At this time, if member B is deleted, track 5.6
Since this becomes an empty state, the present invention updates the VTOC and writes track 5.6 into the lowest extent n.

Note that due to the deletion of member B, the number of each extent below member B is decremented by 1.
The OC is in the state shown in FIG. 4(B).

Note that since the member section is used in the order of the extents written in the VTOC, this empty track 5.6 will be ranked at the lowest position as shown by the arrow in FIG. 4(C).

〔Effect of the invention〕

According to the present invention, for example, when updating a member of a partitioned data set, it is checked whether each track has been released,
If each track is released, the VTOC and directory are updated to make the track usable again, so that files, that is, magnetic disks, can be used effectively without special condensation processing.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the principle of the present invention. FIG. 2 is a configuration diagram of an embodiment of the present invention. FIG. 3 is an explanatory diagram of operation. FIG. 5 is an explanatory diagram of the segmented data set. 1- File 2- Partitioned data set 3-VTO
C4--Processor 5--Directory update section 6--Data invalidation processing section 7-=VTOC update section

Claims (1)

[Claims] A partitioned data set having a directory part and a member part,
VTOC in which the extents of the partitioned dataset are filled
is provided, and a file section (1
) and a processor (1) that updates the file section (1), the data processing device includes a directory update unit (5), and a data invalidation unit that detects that at least one track unit becomes empty during the data update process. a processing means (6); and a VTOC update means (7) that, when at least one track unit becomes vacant during data update processing, sets this vacant track as the lowest extent of the extents of the VTOC.
In addition to writing the number of tracks used by a member in the directory section, when at least one track unit becomes free during member update processing, it is placed at the bottom of the extent so that the free extent can be reused. A partitioned data set update method characterized by: