Speaker
Dr
Timm Steinbeck
(Institute of Physics)
Description
For the ALICE heavy-ion experiment a large cluster will be used to
perform the last triggering stages in the High Level Trigger. For the
first year of operation the cluster consists of about 100 SMP nodes
with 4 or 8 CPU cores each, to be increased to more than 1000 nodes
for the later years of operation. During the commissioning phases of
the detector, the preparations for first LHC beam, as well as during
the periods of first LHC beam, the HLT has been used extensively
already to reconstruct, compress, and display data from the different
detectors. For example the HLT has been used to compress SDD data by a
factor of 15, lossless, on the fly at a rate of more than 800 Hz. For
the TPC the HLT has been used to reconstruct tracks online and show
the reconstructed tracks in an online event display. The event display
can also display online reconstructed data from the Dimuon and PHOS
detectors. For the later detector a first selection mechanism has also
been put into place to select only events for forwarding to the only
display in which data has passed through the PHOS detector.
In the talk we will present experiences and results from these
commissioning phases.
Author
Dr
Timm Steinbeck
(Institute of Physics)
