The Extented Archiver in DOOCS
H.Keller* (DESY)
At the FLASH (Free-Electron Laser in Hamburg) about 30, 000 data channels had been permanently archived. For the XFEL about a factor of 10 times of this is expected. Because of that huge amount each DOOCS server has its own archiver to store and retrieve the filtered data in a history file with one ring buffer per channel and an additional fast memory ring buffer to see the noise on the signal. So far only the data type 'float' had been stored. The new DOOCS archiver can store 15 different data types and generates for 3 of them ' the data types which can be filtered - thumbnail data to enable a quick overview. Now optionally there is the possibility to store in the new additional long term archiver those data that would be overwritten in the ring buffer. The filter thresholds had to be set manually before. The new optional auto filter permanently analyses the data values and readjusts the filter parameters to obtain the desired data compression.