KR100656762B1 - Method for searching a position to be recorded with data in a memory - Google Patents

Abstract

A method for searching a new position to write data and writing the data to the searched position in a memory is provided to realize fast database management in a small device, like a mobile terminal, having a low data processing speed and minimize a memory part not used for writing by searching the position to write the data in the shortest time. Information written in a writing area set by matching with each data bank is searched. The writing area includes the information for the maximum number of continuously arranged sectors among the sectors not including the written data. The data bank having the maximum number over the number of sectors of the data to be written is searched and determined. The position of the continuously arranged sectors is searched in the determined data bank. The data to be written is written to the searched position.

Description

Method for searching a position to be recorded with data in a memory}

1 to 4 are diagrams sequentially illustrating a process of retrieving data and a data recordable position and data recording process according to the present invention; and

FIG. 5 is a diagram illustrating a specific search process for each sector of data bank 1 in FIG. 1.

The present invention relates to a method for retrieving a position where data can be newly recorded in a memory. More particularly, the present invention relates to data management by quickly retrieving a recordable position and recording data according to the size of data to be recorded in the memory. The present invention relates to a search and recording method capable of shortening a recording position search time.

Small devices such as mobile phones have much slower data processing speeds than desktop computers. The most important factor affecting the processing time of data in such a small device is related to the Database Management System (DBMS), and in particular, finding an optimal location for writing new data to memory in the device. That is, as data is repeatedly recorded and deleted in the memory, there are mixed portions in which the current data is recorded and unrecorded portions in the memory. In this situation, in order to record new data, the portion where no data is recorded is recorded. The location should be searched to allow enough space to accommodate the newly recorded data. At this time, a very large time is required in the process of searching for such a location, which leads to an increase in the time required for recording, which makes the user feel a great inconvenience.

Representative methods of data recordable position retrieval for conventional memory management are a scanning method and a pre-defined memory method.

In the scanning method, each sector in the memory is sequentially scanned from the first sector to find a position where no data is recorded in two consecutive sectors if, for example, the size of the data to be currently recorded occupies two sectors. In this way, the data is recorded at the found position. However, this method requires scanning all sectors in the memory sequentially, so that when a sector large enough to record data is found at the end of the search order, the time required for searching becomes very long.

In the predefined memory method, the memory space is temporarily reserved to find an optimal location. However, there is a problem in that the memory cannot be secured indefinitely, and the utility of memory management is very low due to the advancement of the memory, which may not be necessary when data is to be recorded.

On the other hand, according to the conventional memory management scheme as described above, there is a problem in that a memory portion which cannot be actually used for writing data is generated as the recording and deleting of data are frequently repeated despite the available memory space.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to search for a location in a memory in which data to be recorded can be recorded in the shortest time, thereby reducing the speed of data processing such as a mobile phone. The present invention provides a method for retrieving and recording a data record position, which enables rapid database management in a small device, and minimizes a portion of memory that cannot be used for data recording.

In order to achieve the above object, the present invention proposes a search / write method of a position where data can be newly recorded in a memory partitioned into a plurality of data banks each composed of a plurality of sectors. The search / recording method of the present invention comprises the steps of: (a) retrieving information recorded in a correspondingly set recording area for each of said data banks, wherein said recording area is arranged successively among said sectors in which said data is not recorded; The retrieving step, in which information on the maximum number of sectors has been recorded; (b) determining the databank found in step (a) that the maximum number is greater than or equal to the number of sectors of data to be recorded currently; (c) searching for a position in the data bank determined in step (b) that is equal to or greater than the number of sectors of the data to be recorded; And (d) recording the data to be recorded at the position retrieved in the step (c).

According to a preferred embodiment of the present invention, if the search result in step (c) finds that the position equal to or greater than the number of sectors of the data to be recorded does not exist in the data bank, repeating from step (b) for another data bank. Is performed. At this time, the information on the maximum number in the recording area of the data bank is modified to match the current state. Such information correction in the recording area may be performed immediately after step (d).

Meanwhile, in the recording area, information on the total number of sectors, which is the total number of sectors of the data bank, and the number of recording sectors, which are the number of sectors in which the data is recorded, may be additionally recorded.

In this case, the step (c) may include: (c-a) detecting the total number of sectors and the number of recording sectors in the recording area of the data bank determined in the step (b); And (cb) if the number of recording sectors is more than half the total number of sectors, the position is first searched for in the sectors disposed later in the search direction in the data bank, and the position in the sectors disposed later in the data bank. Searching for the position in the sectors disposed in the first half of the search direction if not found, and searching for the position according to the search direction if the number of recorded sectors is less than half of the total sectors; Can be configured.

According to the present invention, since the retrieval time of a location in the memory where data to be recorded can be recorded is significantly shortened, it is possible to quickly manage a database, especially in a small device such as a mobile phone, in which a slowdown in data processing is a problem. The possibility of intensive writing and erasure of repetition for a particular sector is small, thereby minimizing the occurrence of memory portions that cannot be used for data writing.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 to 4 are diagrams sequentially illustrating a process of retrieving a data and a data recordable position and a data recording process according to the present invention.

The memory in which data is to be written is divided into a plurality of data banks (data bank 1, data bank 2, data bank 3, ...), and each data bank is composed of a plurality of sectors. In this embodiment, as shown in Figs. 1 to 4, one data bank is composed of 10 sectors. However, the number of sectors in each data bank may be set differently, and the number of sectors for each data bank is different. It may be set to be different. One sector is preferably set to a size at which a certain amount of data can be recorded.

One recording area is associated with each data bank. Each recording area has a field called Description as shown, and the numbers (i.e., 1, 2, 3, etc.) recorded in this Description field indicate the number of the corresponding data bank. This recording area is provided for recording information on each data bank, and is recorded in a predetermined portion of the memory.

In addition to the Description field, the recording area includes a Total field, an Empty Max field, and a Filled field.

The Total field is a field in which information on the total number of sectors, which is the total number of sectors of a corresponding data bank, is recorded. In the case where the data banks are configured to have 10 sectors as in the present embodiment, the total number of sectors in one data bank is 10, and thus a number "10" is recorded in the Total field.

The Empty Max field is a field in which information on the maximum number of sectors consecutively arranged among the sectors in which data is not recorded in the corresponding data bank is recorded. For example, in the data bank 1, data is recorded in the first four sectors and the sixth and seventh sectors, and no data is recorded in the fourth and eighth to tenth sectors (i.e., new recording of data is performed. Possible state). Since the maximum number of sectors consecutively arranged (that is, the eighth to tenth sectors) among the sectors in which no data is recorded is three, a number "3" is recorded in the Empty Max field. Similarly, "2" is recorded in the Empty Max field of Databank 2 and "4" is recorded in the Empty Max field of Databank 3.

In the Filled field, information on the number of recording sectors, which is the number of sectors in which data is recorded in a corresponding data bank, is recorded. For example, in the data bank 1, since data is recorded in six sectors, "6" is recorded in the filled field of the data bank 1.

When new data is to be recorded in the memory configured as described above, a process of searching for a location to be recorded and writing data to the searched location is as follows.

First, when data of two sector sizes is added and newly recorded, as shown in FIG. 1, information of the recording area is first retrieved. That is, first, the value of the field is queried in the empty max of each data bank among the information recorded in each recording area, and a data bank whose value is greater than or equal to "2" which is the number of sectors of data to be recorded currently is determined. The value of the Empty Max field is sequentially searched from the recording area of the data bank 1, and at this time, the value of the empty max of the data bank 1 satisfies this condition as "3", so the data bank 1 is determined as the data bank in which new data is to be recorded.

Then, each sector of data bank 1 is searched for a position that is equal to or greater than the number of sectors of data to be recorded. This position is determined as a position where two or more sectors are continuously empty because the number of sectors of data to be recorded is two. Therefore, in the same state as the data bank 1 of FIG. 1, the eighth sector and the ninth sector (or the ninth sector and the tenth sector) will be determined as positions to be recorded.

By recording the data added to the determined position in this way, the optimum position search of the data record and the data recording at the retrieved position are completed. When the new recording of data is completed, the state of data bank 1 is changed as shown in FIG.

On the other hand, as the state of the data bank 1 is changed as shown in Fig. 2, in the description area 1 of the data bank 1, the value of Empty Max should be changed to 1 and the value of Filled should be modified to 8.

The information modification process of this recording area is performed after data recording is completed. At this time, the information correction in the recording area may be performed immediately after the data recording is completed. However, in the present embodiment, the information is corrected at the next position search instead of immediately after the data recording is completed in order to further shorten the searching and recording time. Illustrate the method. This will be described with reference to FIGS. 2 to 4.

In the state as shown in FIG. 2, when the data of three sector sizes is added to be newly written in the memory, for example, as shown in FIG. 2, the same process as described above is first performed.

That is, first, the recording area is searched to determine a data bank having an Empty Max value of 3 or more. Since the information in the recording area of the data bank 1 has not been modified yet, in the state of FIG. 2, the data bank 1 first meets these conditions and the data bank 1 will be determined as the data bank in which data will be recorded.

Then, as described above, the sectors in the data bank 1 are searched to find three empty positions. However, in the state of FIG. 2, such a location does not exist and thus the search result will not be found. If it is determined that the position to be recorded is not found as described above, the data storage process is repeatedly performed for the other data banks (i.e., starting from the data bank 2) from the above-described information inquiry process of the recording area.

At this time, before the information retrieval process of the recording area is repeated, the information in the recording area of the data bank 1 is modified to match the state of the current data bank 1. That is, as shown in Fig. 3, in the recording area for data bank 1, the value of Empty Max is modified to 1 and the value of Filled is modified to 8.

On the other hand, when the search of the recording area is repeatedly performed, data bank 2 is not determined as the data bank to which data is to be recorded because the value of Empty Max is "2", and data bank 3 is to be recorded because the value of Empty Max is "4". Determined as a databank. Then, for each sector of databank 3 determined as the databank to which data is to be written, three sectors are successively searched for empty positions, and accordingly, the seventh through ninth sectors (or eighth through tenth sectors) in databank 3 are retrieved. Is determined as the position where data is to be recorded. As data is recorded at the position determined as described above, the state of the data bank 3 changes as shown in FIG. 4.

As described above, in the present embodiment, the information of the recording area of the data bank 3 is not immediately modified, and it is determined that the current state of the data bank 3 is different from that recorded in the recording area when retrieving a position for new recording of another data. In this case, the information of the recording area is modified.

According to the present invention as described above, first, a databank capable of accommodating the size of data to be recorded through the information of the recording area is first determined, and a position to be recorded is determined by searching for sectors in the determined databank. Therefore, the speed is significantly faster than that of the conventional scanning method and the efficient management of the memory is not impaired as compared with the conventional memory system. In addition, since there is no problem of intensive and frequent data writing and erasure for a particular sector, the occurrence of unusable memory parts is reduced.

Also, as in the present embodiment, the operation of modifying the information in the recording area at every retrieval and recording is performed by changing only the data bank which is determined to not reflect the current state in the next retrieval without immediately changing the recording area information. It will not perform. Therefore, the time required for the correction of the recording area information does not occur every time, so that the time for searching and recording is shortened.

Meanwhile, in the above-described embodiment, the searching process of the sectors in each data bank after the data bank to which data is newly written is not described in detail, but the searching process of the sectors in each data bank is similar to the conventional scanning method. It is also possible to employ and also employ the following manner.

FIG. 5 is a diagram illustrating a specific search process for each sector of data bank 1 in FIG. 1.

First, the value of the Total field and the value of the Filled field are detected in the recording area of the determined data bank (i.e., data bank 1) in which the inquiry result data of the recording area is to be recorded. Then, it is determined whether the value of Filled is more than half of the value of Total. Since the value of Total represents the total number of sectors in the data bank and the value of Filled represents the number of sectors in which data is currently recorded, this determination is the process of determining whether more than half of the sectors have recorded data. Becomes

Typically, in one data bank, data is sequentially recorded from the first sector in the search direction (recording direction) when data is recorded. Therefore, when the number of currently recorded sectors is more than half of the total number of sectors, it is placed in the first half of the search direction in the data bank. There is a high probability that data has already been recorded in the sectors (1st through 5th sectors) and there is a low probability that data has already been recorded in the sectors (6th through 10th sectors) placed in the latter half of the search direction. Therefore, if the value of Filled is more than half of the value of Total, the position where data can be written is first searched in the sectors arranged in the latter part of the search direction in the data bank, and the position is determined in the sectors arranged in the latter part. If it is not searched, a search operation of this position is performed in sectors arranged in the first half in the search direction. If the value of Filled is less than half of the value of Total, the position where data can be recorded is searched according to the original search direction.

As shown in FIG. 5, since data bank 1 is more than half (that is, 6/10> 1/2), the first search is performed on the second half, and the second search is performed on the first half when the proper position is not found on the second half. Is done. In the current structure of Databank 1, the secondary search is not performed because the proper location is found in the second half.

Looking at this process, it can be seen that the search time is significantly reduced compared to the case of sequentially searching from the first sector along the search direction. This process also lowers the probability of intensive write and erase repetition for a particular sector, and thus serves to significantly reduce the likelihood of an unusable memory portion.

According to the statistical simulation results, the rate of occurrence of Fregmentation (unusable memory part) is lowered to within 5%, confirming the memory management effectiveness, and confirming that the overall retrieval speed is also increased by five times compared to the conventional scanning method.

According to the present invention, since the retrieval time of a location in the memory where data to be recorded can be recorded is significantly shortened, there is an advantage that rapid database management is possible, particularly in a small device such as a mobile phone, in which the speed of data processing is slow .

Further, according to the present invention, since the possibility of intensive writing and erasure of a specific sector is less likely to be repeated, there is an advantage that the occurrence of a memory portion which cannot be used for data writing is minimized.

In the above, the preferred embodiment of the present invention has been illustrated and described, but the present invention is not limited to the specific embodiments described above, and the technical spirit of the present invention and the following by those skilled in the art to which the present invention pertains. Various modifications and variations will be possible within the equivalent scope of the claims set forth herein, and such variations will fall within the protection scope of the present invention.

Claims (6)

A retrieval / write method of a position where data can be newly recorded in a memory partitioned into a plurality of data banks each composed of a plurality of sectors, (a) retrieving information recorded in a correspondingly set recording area for each of the data banks, wherein information on a maximum number of the sectors arranged consecutively among the sectors in which the data is not recorded is recorded in the recording area; The retrieval step is recorded; (b) determining the databank found in step (a) that the maximum number is greater than or equal to the number of sectors of data to be recorded currently; (c) searching for a position in the data bank determined in step (b) that is equal to or greater than the number of sectors of the data to be recorded; (c-1) when the search result in step (c) finds that the position equal to or greater than the number of sectors of the data to be recorded does not exist in the data bank, the maximum number in the recording area of the corresponding data bank is determined. Modifying the information and repeating the steps from step (b) for the other data banks; And (d) recording the data to be recorded at the retrieved position when the position as the result of the retrieval in step (c) is found to be present in the data bank which is equal to or greater than the number of sectors of the data to be recorded; Search / recording method comprising a. delete delete delete The method of claim 1, A retrieval / recording method, characterized in that information is further recorded in the recording area corresponding to the total number of sectors, the total number of sectors of the sector, and the number of recording sectors, the number of sectors on which the data is recorded. . The method of claim 5, In step (c), (c-a) detecting the total number of sectors and the number of recording sectors in the recording area of the data bank determined in the step (b); And (cb) when the number of recording sectors is at least half of the total number of sectors, the position is first searched in the sectors arranged in the latter half of the search direction in the data bank, and the position is searched in the sectors arranged in the latter half. If not, searching for the position in the sectors arranged in the first half of the search direction, and searching for the position according to the search direction if the number of recorded sectors is less than half of the total number of sectors; Search / recording method comprising a.

Images