User Manual

Working with Projects
the application utilize more than 85% without caching the application will not
be able to cache any screens and therefore not experience faster screen switching
times.
Trend ViewersandDataLoggers
Several trend vie wers can show data from the same log item.
In order to optimize performance in the panel, it is strongly recommended to place
all log items logged on the same frequency/event in the same data logger or at least
reduce the amount of data loggers.
Try to avoid having one data logger for each trend viewer.
Data logging in general have impact on the performance. Reconsider the data
logger settings, the log frequency and the amount of log items. Heavy data logging
will increase the CPU usage and will influence performance across the whole
application.
Data logging is queued up if more logging is done than the database can handle
at the moment. If the queue reaches a too high level, the warning “Data logging
has too high load. Data might be lost.” isshownonthescreeninthetopleftnotifier
window. If the queue reaches a critical level, there is a risk that the system will
malfunction. If this happens, alarm and data logging are turned off, the error
message “Data logging is overloaded. Data logging is now disabled.” isshowninthe
dialog and the system tag Database Error Active is set. The system tag Database
Error Message contains the error message.
The system tag is not reset by the system. It is up to the user to re
setitwhenthe
system error is taken care of.
Alarm and data logging are turned on again when the queue is below the critical
level.
StorageMedia
If the storage media reaches a critically low level, there is a risk that the system
will malfunction. If this happens, alarm and data logging is turned off. The error
message “99% of disk used. Alarm logging is now disabled. Data logging is now
disabled.” is shown and the system tag Database Error Active is set. The system tag
Database Error Message contains the error message.
The system tag is never reset by the system. It is up to the user to reset it when the
system error is taken care of.
Alarm and data logging are turned on again when the storage usage is below the
critical level.
You can avoid this situation by using the Max Size setting for the database. When
the limit is reached you will be informed by a warning message.
Database
If there is a risk of the database running out of storage media, then a warning is
shown on the screen. If the usage reaches a critical level, risking the system to crash,
alarm and data logging is turned off, an error message is shown and the system tag
Database Error Active is set. The system tag Database Error Message contains
the error message. Alarm and data logging are turned on again when the storage
usageisbelowthecriticallevel.
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