The Historian category provides status information about the historic data that is being stored. The status information is useful for identifying which points, if any, are logging excess data.
The status for the historic data is categorized as:
- Id—Indicates the type of historic data. The Id can be:
- Event—ClearSCADA events that are stored in the Event Journal.
- ConfigChanges—Historic data created as a record of configuration changes.
- Raw—Historic data that has been received from points.
- Modified—Historic data that has been modified by operators or engineers.
- Annotation—Annotations that have been inserted by operators or engineers.
- Suppression—Historic data that relates to suppressed alarms. A historic record is created whenever alarms are suppressed on a point (and also when alarms stop being suppressed on a point). For more information on alarm suppression, see Alarm Suppression in the ClearSCADA Guide to Alarms.
- His Error—The number of errors per region of historic data. This should be 0. If your system has a number other than 0, this indicates abnormal conditions and you should contact Schneider Electric for assistance.
- Total Memory Usage—The total amount of memory used to store the records and database information.
- Record Size—The size (in bytes) of a single record.
- Total Stream—The number of streams used to transfer the directories for historic data. When the historic data is transferred, it is separated into directories. Each directory requires approximately 1 stream.
- Total Primary File—The total number of files that are on disk and represent the time period defined for the primary historic granule index. There is 1 file per granule (a period of time, for example, a week). If the long term storage index feature is not being used, the Total Primary File entry is the total number of historic files on disk (see Reduce the Size of the Historic Index in the ClearSCADA Guide to Server Administration).
- Total Secondary File—The total number of files that are on disk and represent the time period defined for the secondary historic granule index. The entry is 0 if the long term storage index feature is disabled (see Reduce the Size of the Historic Index in the ClearSCADA Guide to Server Administration).
- Total Record—The total number of historic records that are stored on the hard disk. If this number increases rapidly, there may be a high server load (see Check for High Load on a ClearSCADA Server).
- Total Data—The total size of the historic data.
- %Flush—The percentage of historic data that has not yet been saved to the hard disk.
- Flush Record—The number of historic records that have not yet been saved to the hard disk.
- Flush Data—Indicates the size of the data that has not yet been saved to the hard disk.
- Read Count—The number of file read operations.
- Write Count—The number of file write operations.
- %Cache—The percentage of historic data that is stored in the cache. The cache is used to store data that is required by a historic display that is currently in use. For example, if the Events List for a specific item is displayed, the cache is used to store all of the historic data that could be shown on the Events List for that item.
- Cache Record—The number of historic records that are stored in the cache, seeDefine the Historic Data Cache Size in the ClearSCADA Guide to Server Administration.
- Cache Data—The size of the historic data that is stored in the cache seeDefine the Historic Data Cache Size in the ClearSCADA Guide to Server Administration.
- Loaded Files—The number of historic files that have been loaded.
- Locked Files—The number of historic files that are locked in the database (cannot be accessed because they are currently secured for use elsewhere, for example, are being used for a Historic search).
- Largest File—The size of the largest historic file.
- Largest File Name—The name of the largest historic file.
- Flush Error—Indicates the number of historic files that could not be written (‘flushed’) to disk. If this is anything other than 0, there is a problem, and the cause of the problem is indicated in the Error Code column.
- Error Code—Shows the result of writing data to file on disk.
- The Error Code is blank if there were no errors writing data to file on disk.
- An Error Code is shown if there are errors writing data to file on disk. The error code relates to the first error that occurred and is an operating system error code. It uses the syntax: <error number> - > <error description>.
- Error File—The name of the first file in which ClearSCADA has detected an error (the error is described in the Error Code column).