JPH1011330A - Log recording method and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To record necessary log information by detecting log information which expires a previously set preserving period, preserving the overwriting of log information on it at the time of existence and generating a new storage part at the time of non-existence to record generated log information. SOLUTION: A recording position deciding part 5 obtains a present date from a present time obtaining part 4, obtains a recording period from a recording period storage part 6 so as to execute calculation and judges whether the period elapses more than the preserving one or not. When the period more than a recording period elapses as the result of the judgement, a partial log information storage part 11 having the oldest and latest log date is decided as the partial log information storage part for executing recording and its leading position is adopted as a recording position. Unless the period more than the recording period elapses, the recording position deciding part 5 permits a management information recording part 8 to generate the new partial log information storage part 11 with the command of a log recording control part 3 and also records received log information at the prescribed position of the partial log information storage part 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a log recording method and a device therefor in various types of information processing apparatuses for saving program execution status, user operation contents, and the like as log information.

[0002]

2. Description of the Related Art Various information processing apparatuses are provided with means for storing program execution status, processing contents, and the like as log information in a recording apparatus. Since the storage amount increases, the occupation amount of the memory device increases. Therefore, conventionally, it has been necessary to perform a backup process of periodically transferring the log information stored in the log file to another storage medium to delete the log information in the log file. Such backup processing and erasing work imposes a considerable burden on the user as the log information increases, and various methods for minimizing the increase in the storage amount of the log information have been conventionally provided. . For example, in a log storage method of a database management system disclosed in Japanese Patent Laid-Open No. 5-108731, a plurality of different log information storage units are provided in log information recording for failure recovery performed when a database is updated, and log information storage is performed. A method has been proposed in which the log information storage means is selectively used according to the size of a free area of a unit (log file). In the error logging method disclosed in Japanese Patent Application Laid-Open No. 5-197597, when the same type of error occurs, instead of recording the details of the error as log information, pointer information indicating an area where the same type of error is stored is stored. To reduce the storage amount of log information.

Further, as a method for preventing a log file from continuously increasing as the operation time of an information processing apparatus increases, round robin writing to a file is generally performed. This method keeps the storage capacity of the log file constant,
When the recording of the log information reaches the end of the file, the log information newly generated from the beginning of the same file is overwritten. As means for solving the above problem, Japanese Patent Application Laid-Open
In the log recording method disclosed in Japanese Patent No. 238550, two log files are provided, and these are stored in a plurality of subsystems S1 to S
Alternate methods have been proposed for logging n. FIG. 12 is a diagram for explaining the log recording method disclosed in the above-mentioned Japanese Patent Application Laid-Open No. Hei 4-238550. This method includes two log files 41 and 42 as shown in the figure, and performs log information recording for a plurality of subsystems S1, S2,... Sn of the information processing apparatus via the storage processing unit 121. A plurality of storage areas R1, R2,.
Rn is assigned to n subsystems and used,
For example, when the storage area R2 is used up, the other log file 42 is similarly divided and used, but at this time, the storage area of the storage area R2 is widened to reduce the frequency of exchange of the two log files, The retention period of information has been extended.

[0004]

However, in the conventional methods disclosed in Japanese Patent Application Laid-Open Nos. 5-108731 and 5-197597, the rate of increase in the log file storage amount is moderate, There is no difference that the log file storage amount gradually increases as the information processing apparatus continues to operate. In either case, the memory capacity is insufficient, and a backup is required as before. Further, in the related art disclosed in Japanese Patent Application Laid-Open No. Hei 4-238550, there is a problem that important log information in the past is erased by overwriting. The present invention has been made in order to solve the problems in the conventional log recording method as described above, and the storage amount of a log file does not increase indefinitely, and important log information in the past is stored. It is an object of the present invention to provide a log recording method that is not erased by overwriting and a device therefor.

[0005]

According to a first aspect of the present invention, there is provided a log recording method for storing log information, comprising a plurality of partial log information storage units for storing log information. An information storage unit, comprising a storage period elapse determining means for determining whether the log information storage period stored in each partial log information storage unit has passed a preset period, and when recording new log information, If there is a free area in the currently selected partial log information storage unit, new log information is recorded in the free area. If no free area remains, the storage period set in advance by the storage period elapse determination unit is used. Detects past log information, overwrites new log information on the relevant log information if it exists, and newly saves partial log information if the relevant log information does not exist. Characterized in that it records the generated log information generated by the parts. According to a second aspect of the present invention, in the log recording apparatus for performing the log recording method according to the first aspect, a storage period setting unit for setting a storage period of the recorded log information is provided. If the set storage period is shorter than the previously set period, the storage elapsed period of each log information is obtained from the last log date and time and the current date and time of each partial log information storage unit, and There is provided a means for extracting a partial log information storage unit whose storage period has elapsed and deleting the partial log information storage unit from the log information storage unit.

According to a third aspect of the present invention, in the log recording method for storing log information, a log information storage unit having a plurality of partial log information storage units for storing log information, and each of the partial log information storage units is stored. Storage time passing judgment means for judging whether or not the set log information storage period has passed a preset period, and when recording new log information, the last log date and time of each partial log information recording unit and the current The respective storage elapsed periods are calculated from the date and time, and if there is an empty area in the currently selected partial log information storage unit, new log information is recorded in the empty area, and the partial log information whose elapsed storage period has elapsed is recorded. If the information is deleted and no free space remains in the selected partial log information storage unit, new log information is overwritten and saved on the log information whose storage period has passed, If available log information does not exist, and recording the generated log information generated by the newly partial log information storage part. According to a fourth aspect of the present invention, there is provided a log recording apparatus for performing the method according to the first or third aspect or the log recording apparatus according to the third aspect, wherein a log recording status storage for storing date and time information relating to a current log recording status. And a log storage capacity calculation unit that calculates a predicted value of a required storage capacity of the entire log information storage unit based on the date and time information, the set storage period, and information on the storage capacity of the partial log information storage unit. It is characterized by having.

[0007]

According to the present invention as described above, according to the first aspect of the present invention, if the partial log information storage unit having the longest storage elapsed time exceeds the preset storage period, the generated log information is not stored. It is recorded in the above-mentioned partial log information storage unit, and when it does not exceed the storage period, it is recorded in a new partial log information storage unit. In the invention according to claim 2, in addition to the above,
When the storage period is changed to a short period, it is determined whether the storage period has elapsed based on the newly set storage period, and if there is a partial log information storage unit whose period exceeds the storage period after the change, the The partial log information storage is deleted from the log information storage. According to the third aspect of the invention, in addition to the operation of the first aspect, if there is another partial log information storage unit whose elapsed period exceeds the set storage period, the partial log information storage unit stores the log information storage unit. Removed from the department. According to the fourth aspect of the present invention, the required total storage capacity of the log information storage unit can be estimated in advance from the storage period.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. FIG. 1 shows the first embodiment of the present invention.
FIG. 2 is a block diagram illustrating a configuration of a log recording apparatus according to an embodiment.
In this embodiment, the log recording device does not include the target program execution unit 21 that generates the log information and the log transmission unit 22 that transmits the generated log information to the log recording device. As shown in the figure, the log recording apparatus according to this embodiment includes a plurality of partial log information storage units 11 for recording log information and a management information storage unit 12 for storing management information relating to each of the partial log information storage units 11. The log information is stored in the configured log information storage unit 1, the log reception unit 2 that receives the log information from the log transmission unit 22, and the partial log information storage unit 11 that is determined by the recording position determination unit 5. A log recording control unit 3 for issuing a command to the log information recording unit 7, a current time acquisition unit 4 for acquiring the current date and time, the acquired current date and time, a final log date and time of each partial log information storage unit 11, and a predetermined record A recording position determination unit 5 that determines which partial log information storage unit 11 to record based on a period (storage period) and the like, and a recording period storage unit 6 that stores the predetermined recording period.
A log information recording unit 7 that records log information in any of the partial log information storage units 11, a management information recording unit 8 that records management information related to the partial log information storage unit 11 in the management information storage unit 12, and And the oldest last log time acquisition unit 9 for detecting the oldest last log date and time from the last log date and time of the partial log information storage unit 11.

The log receiving unit 2, the log recording control unit 3, the current time acquiring unit 4, the recording position determining unit 5, the log information recording unit 7, the management information recording unit 8, and the oldest last log time acquiring unit 9
Is mainly composed of a ROM with a built-in CPU and programs, and the recording period storage section 6 is provided in, for example, a RAM.

FIG. 2 is a diagram showing a detailed configuration of the log information storage unit 1. As shown, the log information storage unit 1 of this embodiment has n partial log information storage units 11 (1). And a management information storage unit 12. Further, the management information storage unit 12 has a partial log information storage unit total storage area.
31, a management information location storage area 32 for recording the storage location of the currently selected partial log information storage unit, and n management information storages corresponding to the n (variable) partial log information storage units 11 Each of the management information storage areas 33 includes an identifier storage area 34 for storing an identifier (such as a file name) for accessing the partial log information storage unit 11 and a current log information area. Area 35 for storing recording position
And the first log time storage area 36 for storing the date and time when the oldest log information # 1 was recorded, and the last log for storing the date and time when the last (latest) log information (the last at this time is log information #i) was recorded. It consists of a time (end log time) storage area 37. FIG. 2 shows that m pieces of log information 38 are recorded in the fixed-length partial log information storage unit 11. That is, each log information 38 (log information # 1 to #m) is one log information generated in the target program execution unit 21.

FIG. 3 is an operation flowchart showing a first embodiment of the present invention. Hereinafter, the operation of the first embodiment will be described with reference to FIGS. First, the log receiving unit 2 sets the log transmitting unit 22
Upon receiving the log information sent from, the log recording control unit 3 checks whether or not there is a recordable free area in the currently selected partial log information storage unit 11 (S1). As a result, if there is an empty area (S1, No), the recording position determination unit 5 determines the currently selected partial log information storage unit 11 as the recording position (S2), and proceeds to step S11. on the other hand,
If there is no free area in step S1, (S
1, Yes), the oldest last log time acquisition unit 9 acquires the last log date and time from each management information storage area 33 of the management information storage unit 12, compares a plurality of last log dates and times, and The log date Tr is extracted (S3). Further, the recording position determination unit 5 acquires the current date and time Tn from the current time acquisition unit 4 (S4), acquires the recording period Tk from the recording period storage unit 6 (S5), and calculates Tn−Tk> Tr. That is, it is determined whether or not the current date and time Tn has passed a predetermined recording period (storage period) Tk or more from the oldest final date and time Tr (S6). As a result of this determination, if the period equal to or longer than the recording period Tk has elapsed (S6, Yes), the recording position determining unit 5 performs partial log information recording in the partial log information storage unit 11 having the oldest final log date and time Tr. The storage position is determined, the head position is set as the recording position (S7), and the process proceeds to step S11. If the period longer than the recording period Tk has not elapsed in step S6 (S6, No), the recording position determination unit 5 sends the new partial log information to the management information recording unit 8 via a command from the log recording control unit 3. The storage unit 11 is generated (S8), and the head position is determined as the recording position (S8).
9) Go to step S10. In step S10, the received log information is recorded at a predetermined position of the partial log information storage unit 11 determined by the recording position determination unit 5 (S10), and the contents of the management information storage unit 12 are further determined according to the determination of the recording position determination unit 5. Is updated (S11).

FIG. 4 is a diagram for specifically explaining the above-described recording position determination method. In this example, the recording period Tk
Indicates the case of 7 days. That is, in the figure, progress (1) is the first log recording, and the partial log information storage unit # 1 is registered in the management information storage unit 12, and January 8
At 14:21 (01081421), it is indicated that log information was recorded at the head position of the partial log information storage unit # 1. In the elapse (2), log information to be stored occurred at 9:10 on January 16, but as a result of the determination, there is no free space (full) in the currently selected partial log information storage unit # 1. First, it is checked whether the log information in the partial log information storage unit # 1 at that time can be overwritten. The judgment was January 16 as described above.
An operation of day 9:10 (Tn)-day 7 (Tk) <January 13 at 10:45 (Tr) is performed, and since the preset period has not elapsed, the log information of # 1 cannot be overwritten. And the partial log information storage unit # 2 is registered in the management information storage unit 12. That is, a partial log information storage unit # 2 is added to the log information storage unit 1, and the log information generated at the head position of # 2 is recorded.

The progress (3) shows a case where log information recording occurs at 11:51 on January 23. At this time, since there is no free area in # 2, the oldest log date and time # 1 The last log date and time of January 13 at 10:45 is extracted as Tr, and #
Check whether 1 can be overwritten. As a result, (Tn-T
k> Tr), and overwriting is possible, so the generated log information is recorded at the head position of # 1. In progress (4), 1
Log information recording occurred at 8:56 on March 27, and at that time # 1
Since there was no free space in the last log date and time, the last log date and time of the oldest log date and time # 2 was extracted as Tr on January 22 at 15:21, and extracted as Tr.
Check whether 2 can be overwritten. As a result, (Tn-T
k <Tr), it is determined that overwriting is not possible, and a new # 3
Is registered, and the generated log information is recorded at the head position of # 3. Similarly, in the progress (5), log information is recorded at the head position of # 2. As described above, according to the first embodiment, it is determined from the already recorded log information whether or not there is any one that has passed the preset recording storage expiration date. Since the information is erased and overwritten thereon, it is possible to prevent the storage amount of the log information storage unit 1 from increasing without limit, and
All log information can be stored for a desired recording period or longer.

FIG. 5 is a block diagram showing a configuration of a main part of a log recording apparatus according to a second embodiment of the present invention. The log recording apparatus shown in this embodiment is obtained by adding a recording period setting unit (storage period setting means) 10 to the configuration of the recording apparatus of the first embodiment. The recording period setting unit 10 includes a CPU and a ROM having a built-in program, and displays a message requesting input of a recording period (storage period) on a display unit (not shown). Is input, and is obtained and set in the recording period storage unit 6. Hereinafter, the operation of this embodiment will be described with reference to the operation flow shown in FIG. First, as described above, when log information is generated and recorded, a message is displayed on the display device so as to input a recording period (storage period), and the recording (storage) desired by the user in response thereto is performed. When the period Tk is input (S21), it is set in the recording period storage unit 6 (S2).
2). The recording position determination unit 5 acquires the current date and time Tn via the current time acquisition unit 4 (S23), and issues a command to the oldest final log time acquisition unit 9 to acquire the oldest final log date and time Tr (S24). ) (See S3 in FIG. 3). Then, the recording position determination unit 5 determines whether or not Tn−Tk> Tr (S
25) If Yes, the partial log information storage unit 11 having the oldest final log date and time Tr is deleted from the log information storage unit 1 (S).
26). After step S26, the process returns to step S24, and Tr is acquired again with the exception of the partial log information storage unit 11. Hereinafter, the process is repeated until it is determined as No in step S25 (S25 → S26 → S24 → S25). If you set a shorter recording period Tk than the previously set period,
Since the partial log information storage unit 11 in which the elapsed time from the last log date and time to the current date and time exceeds the recording period (storage period) appears, these can be deleted from the log information storage unit 1. Finally, the content of the management information storage unit 12 is updated (S
27), this operation flow ends.

FIG. 7 shows a specific example when the recording period Tk is changed from 7 days to 4 days. In FIG. 7, progress (1) indicates three partial log information storage units # 1, # 2, and # 3.
Has been registered, and # 3 is in the selected state.
It is assumed that it is immediately after the recording of the log information generated at 16:00 is completed. Note that Tk is 7 days. Progress (2)
Immediately after the log information recording that occurred at 14:46 on February 27, the recording period Tk was changed from 7th to 4th. Whether # 1 and # 2 can be deleted, that is, Tn-Tk
(4th)> It is determined whether Tr is satisfied or not.
Since n-Tk> Tr, it is deleted, and # 1 is Tn-Tk
<Tr, so it is saved. As described above, according to this embodiment, the user can set the recording period (storage period) according to the situation.
Can be freely changed, so that the balance between the storage amount limitation of the log information storage unit 1 and the log information storage period can be appropriately set.

FIG. 8 is a diagram showing an example of an operation flow in the third embodiment of the present invention. Hereinafter, FIG.
The operation of the embodiment will be described. When the recording of the log information becomes necessary, the current date and time Tn is acquired (S31, S4 in FIG. 3) and the recording period Tk is acquired as in the case of the first embodiment already described with reference to FIG. (S32, S5 in FIG. 3). Then, the currently selected partial log information storage unit 11
If there is a recordable free area (S33, No), the oldest final log date and time Tr is acquired (S34, S in FIG. 3).
3). Subsequently, the recording position determination unit 5 determines the acquired Tn, T
It is determined whether Tn−Tk> Tr based on k and Tr (S35), and if Yes, the oldest final log date and time Tr
Is deleted from the log information storage unit 1 (S36), and the process returns to step S34 to determine whether or not there is any remaining partial log information that satisfies Tn-Tk> Tr. As long as there is information, the deletion of the corresponding partial log information is repeated in order from the oldest one. That is, in this embodiment, if log information recording occurs, even if a recordable free area remains in the selected partial log information storage unit 11, the time from the last log date Partial log information whose period exceeds the storage period (recording period) is detected, and if there is a corresponding one, that part is deleted from the log information storage unit 1.

As described above, when the partial log information storage unit 11 that satisfies Tn−Tk> Tr disappears (S35, No),
The recording position determination unit 5 determines an area following the latest recording area of the selected partial log information storage unit 11 as a writing position area (S37), and proceeds to step S43. If it is determined in step S33 that there is no free area (S33, Yes), the oldest final log date and time is acquired in the same manner as above (S38), and whether or not Tn−Tk> Tr is determined. It is determined (S39), and as a result of the above determination, when the elapsed period exceeds the recording period (storage period) (S39, Yes), this area is determined as the recording position of the newly generated log information (S4).
0), and proceed to step S43. On the other hand, if there is no record whose elapsed period has reached the recording period in step S39 (S39, No), steps S41 to S44 are executed. These steps are performed in the first embodiment (FIG. Since the steps are exactly the same as steps S9 to S12 of 3), the description is omitted.

FIG. 9 is a diagram showing a concrete example of the third embodiment of the present invention. In progress (1), when the partial log information storage unit # 3 is being selected, and when log information recording occurs at 10:15 on January 28, there is a recordable empty area in # 3, and 3 shows that new log information could be recorded. At this time, # 2 having the oldest final log date and time Tr
When it was determined whether or not Tn−Tk> Tr, T
Since n-Tk <Tr, both # 1 and # 2 are stored as they are. In progress (2), when log information recording occurs at 13:28 on January 30 while # 3 is still selected,
There is a recordable empty area in # 3, which indicates that new log information has been recorded in this area # 3. In addition, Tn- # 2 has the oldest last log date and time Tr.
When it was checked whether Tk> Tr, Tn−Tk>
Since it was Tr, it was also determined whether or not Tn-Tk> Tr for # 1, and as a result, for # 1, Tn-Tk <Tr
Tr, # 2 is deleted from the log information storage unit 1 and # 1 is stored. In progress (3), continue with # 3
When log information recording occurs at 11:44 on February 3 during the selection of, the recordable empty area exists in # 3, indicating that new log information could be recorded in # 3. But # 1
As a result of the determination about, Tn−Tk> Tr, so that # 1 is deleted. As described above, according to this embodiment, if there is a partial log information storage unit 11 in which the elapsed time from the last log date and time to the current date and time exceeds the recording period (storage period) every time log information recording occurs, Since the part is deleted from the log information storage unit 1, it is more effective in limiting the storage amount of the log information storage unit 1.

FIG. 10 is a block diagram showing a configuration of a main part of a log recording apparatus according to a fourth embodiment of the present invention. The log recording apparatus shown in this embodiment further includes a log recording status storage unit 13 and a log storage capacity calculation unit 14 in addition to the configuration of the first embodiment shown in FIG. ) Is calculated so as to calculate the total storage capacity of the log information storage unit 1 necessary to secure (1). Note that the log recording status storage unit 13 is provided in a RAM or the like, and the log information storage unit 1
The data relating to the log recording status required to calculate the total storage capacity of the server is stored. The log storage capacity calculation unit 14
Is composed of a ROM with a built-in CPU and programs. FIG. 11 shows an operation flow of the fourth embodiment of the present invention. The operation of this embodiment will be described below with reference to FIG. First, the log storage capacity calculation unit 14 determines that the recording period T
k is acquired (S51), and the expected recordable period Mi is calculated for each partial log information storage unit 11 by the following equation (S51).
52). Mi = (nLog / iLog) × (tLast-tFirst) In the above, nLog is the maximum number of log information that can be recorded in the partial log information storage unit 11, and iLog is the partial log information storage unit.
11, the first log date and time, and tLast is the last log date and time. The meaning of this expression is the period (tLas) required to record iLog numbers.
From (t-tFirst), a period required for recording nLog (expected recordable period) is obtained by proportional calculation. NLog, iLog, tLa required for calculation
Values such as st and tFirst are stored in each partial log information storage unit.
It is stored in the log recording status storage unit 13 for each 11. next,
The log storage capacity calculation unit 14 calculates the required number nFile of the partial log information storage units 11 by the following equation (S53). nFile = Tk / (avg [Mi]) In the above, avg [Mi] represents the average value of Mi.
Using the result of the above calculation, the required total storage capacity sSpc of the log information storage unit 1 is calculated by the following equation (S54). sSpc = sCtrl + nFile × nLog × sLo
g In the above, sCtrl is the required storage capacity of the management information storage unit 12, and sLog is the data amount of one log information.
Finally, the calculated value of sSpc is output to a display unit or a printer (S55).

Hereinafter, a specific example of obtaining the above sSpc with respect to the progress (1) shown in FIG. 9 will be described. However, # 1
NLog = 100 for # 2 and # 2, nLog for # 3
g = 25, sCtrl = 256 bytes, sLog = 32
Byte. Mi of # 1 = (100/100) x (18:35 on January 26-11:51 on January 23) = 6:44 on March 3 Mi of # 2 = (100/100) x (1 (15:21 on the 21st of the month-9:10 on the 16th of January) = 6 hours and 11 minutes on the 5th Mi of # 3 = (100/25) x (10:15 on January 28-8 on January 27) (Time 56 minutes) = 4 days 5 hours 16 minutes nFile = (24 hours × 7) ÷ 96.07 Time = 1.75 Integer converted to nFile = 2. However, since the frequency of occurrence of log information varies, nFile should be checked with a margin. = 3. sSpc = 256 + 3 × 100 × 32 = 9856 (bytes) As described above, according to the fourth embodiment, the total storage capacity required before the recording period (storage period) can be estimated in advance. The total storage capacity of the log information storage unit 1 can be determined.

[0021]

As described above, according to the present invention, according to the first aspect of the present invention, when the storage elapsed time of the oldest log information exceeds a preset period, the generated log information is replaced with the partial log information. The information storage unit is overwritten and saved, and if there is no one that has exceeded the storage period, a new partial log information storage unit is added and recorded, so the storage capacity of the log information storage unit is unlimited. It is not increased and a necessary storage period of the log information is secured. According to the second aspect of the present invention, the storage period can be arbitrarily changed in addition to the above, and the elapse of the storage period of the recorded information is determined based on the newly set period. Since the configuration is such that the log information is deleted from the log information storage unit, the increase in the log storage capacity is more effectively limited. Further, according to the third aspect of the present invention, the elapsed time since the last log information was recorded exceeds the storage period,
In addition, if there is a partial log information storage unit in which the generated log information is not written, the partial log information storage unit is deleted from the log information storage unit, so that the increase in the log storage capacity is further effectively limited. In the invention according to claim 4,
Since the required total storage capacity of the log information storage unit can be estimated in advance from the storage period, an appropriate storage period and the total storage capacity of the log information storage unit can be determined.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a log recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a main part of a log recording apparatus according to a first embodiment of the present invention.

FIG. 3 is an operation flowchart of the log recording apparatus according to the first embodiment of the present invention;

FIG. 4 is a diagram illustrating a specific example of a log recording device according to a first embodiment of the present invention.

FIG. 5 is a block diagram illustrating a configuration of a main part of a log recording apparatus according to a second embodiment of the present invention.

FIG. 6 is an operation flowchart of a log recording apparatus according to a second embodiment of the present invention.

FIG. 7 is a diagram illustrating a specific example of a log recording apparatus according to a second embodiment of the present invention.

FIG. 8 is an operation flowchart of a log recording apparatus according to a third embodiment of the present invention.

FIG. 9 is a diagram illustrating a specific example of a log recording apparatus according to a third embodiment of the present invention.

FIG. 10 is a configuration block diagram of a main part of a log recording device according to a fourth embodiment of the present invention.

FIG. 11 is an operation flowchart of a log recording apparatus according to a fourth embodiment of the present invention.

FIG. 12 is a configuration block diagram illustrating an example of a conventional log recording device.

[Explanation of symbols]

1 log information storage unit, 2 log reception unit, 3 log recording control unit, 4 current time acquisition unit, 5 recording position determination unit, 6
Recording period storage unit, 7 log information recording unit, 8 management information recording unit, 9 oldest final log time acquisition unit, 10 recording period setting unit, 11 partial log information storage unit, 12 management information storage unit, 13
Log recording status storage unit, 14 log storage capacity calculation unit

Claims (4)

[Claims] 1. A log recording method for storing log information, comprising: a log information storage unit having a plurality of partial log information storage units for storing log information; and a log information storage period stored in each of the partial log information storage units. A storage period elapse determining means for determining whether or not a preset period has elapsed, and when recording new log information, if there is an empty area in the currently selected partial log information storage unit, the empty area In the case where there is no free space remaining, the storage period elapse determining means detects the log information that has passed the storage period set in advance, and if the corresponding log information exists, A log recording method, which overwrites and saves new log information and, if there is no corresponding log information, creates a new partial log information storage unit and records the generated log information. Law. 2. A log recording apparatus for carrying out the log recording method according to claim 1, further comprising: a storage period setting unit for setting a storage period of the recorded log information, wherein the storage period is set by the storage period setting unit. If the period is shorter than the previously set period, the storage elapsed period of each log information is obtained from the last log date and time and the current date and time of each partial log information storage unit, and the storage period after the change elapses. A log recording apparatus, comprising: means for extracting the partial log information storage unit and deleting it from the log information storage unit. 3. A log recording method for storing log information, comprising: a log information storage unit having a plurality of partial log information storage units for storing log information; and a log information storage period stored in each of the partial log information storage units. A storage period elapse determining means for determining whether or not a preset period has elapsed is provided. When new log information is recorded, each storage progress is determined from the last log date and time and the current date and time of each partial log information recording unit. The period is calculated, and if there is an empty area in the currently selected partial log information storage unit, new log information is recorded in the empty area, and the partial log information whose storage elapsed period has elapsed is deleted, and the selected log information is deleted. If there is no free space remaining in the partial log information storage unit, new log information is overwritten and saved on the log information whose storage period has expired, and there is no free space and there is log information that can be deleted. If not, a log recording method characterized by newly generating a partial log information storage unit and recording generated log information. 4. A log recording device for performing the method according to claim 1 or 3, wherein the log recording status storage unit stores date and time information relating to a current log recording status. Log storage capacity calculating means for calculating a predicted value of the required storage capacity of the entire log information storage unit based on the date and time information, the set storage period, and information on the storage capacity of the partial log information storage unit. Log recording device.