How does the openPDC handle the locally cached measurements?
If the openPDC has cached measurements for a historian that does respond, the openPDC will push the entire cache of data to the historian as soon as the historian is reconnected – this data will be pushed to the historian as quickly as possible to relieve memory pressure. If the historian continues to not respond, the openPDC will start dropping the oldest data in order not to exceed a user configurable number of points in memory (this to avoid possible out-of-memory errors). The settings to control the number of points maintained in memory can be found in the openPDC configuration file (SOURCEDIR\Build\Output\Debug\Applications\openPDC\openPDC.exe.config where SOURCEDIR is the root directory of the source code). These numbers can be adjusted to a much higher levels on 64-bit machines with large amounts of available memory. IMPORTANT: The openPDC will send the entire cached measurement queue to the archiver therefore it is imperative that the space taken by cached points on the openPDC
