Argonne : R. Blair
CERN : P. Golonka, K. Korcyl, S. Wheeler
Michigan : M. Abolins
NIKHEF : R. Scholte, J. Vermeulen
UCL : R. Cranfield
1. Paper modeling : In June nesults obtained with new menus, parameters etc, should be made available. The mapping of the ROBs on the detectors will be kept the same as used for the TP. For the data volumes only for the SCT and for low luminosity the data volume per ROB will be changed from 250 to 400 Bytes. For intermediate luminosity (2 * 10 **33) it will be assumed that for the inner tracker all data volumes per ROB are a factor of two larger than those for low luminosity. Taking into account network overhead incurred by the TCP/IP protocol does not seem to be possible in a straightforward way (as was hoped), so this will not be done. For the ROBs the parameters will be kept the same as used for the TP. Other assumptions will be as discussed in previous meetings. J. Vermeulen aims to send a first version of a document with new results in the first week of June to M. Abolins.
2. ROS modeling : R. Cranfield is completing a UML description of the "fully collapsed" version of the software, and needs details of the LVL2 interface code, to be provided by D. Francis. J. Vermeulen noted that there is a new version of Together, R. Cranfield is still using the old version as the new version does not seem to offer much advantage and as the problems he had with the older version - perhaps due to a different way of working - seem to have more or less disappeared.
3. Data Collection modeling : K. Korcyl and P. Golonka have continued with the model for the TCP/IP stack and with making relevant measurements. A poster for the RT2001 conference has been made, see this web page. P. Golonka showed some results. He also showed a figure with results on the CPU utilization when using the "select" call as a function of the number of open connections. For a 400 MHz CPU 100 % CPU utilization occurred for 300 connections. Results of the measurements on switches will also be presented in a paper at the RT2001 conference.
4. HLT modeling : S. Wheeler is still waiting for a new PC to arrive. She looked at G. Lehmanns code, which was incorporated by M. Dobson in at2sim. This needed revision. The network interfaces have been replaced and a common message format is now used. The revised code has been tested. S. Wheeler will contact H.P. Beck to find out about the foreseen message flow and actions of the DFM. J. Vermeulen asked to keep the group informed with respect to new developments.
5. Reference testbed model : The completion of the document describing the results is delayed. J. Vermeulen will give the paper model priority and then complete a draft on the results and send it to K. Korcyl.
6. Ptolemy : There was nothing to report, apart from ununderstood problems with scripts in Rumania. The help of the Ptolemy developers has been asked for solving the problems.
7. Simdaq : There was nothing to report.
8. "Chiba City" : A number of succesful runs has been made, some runs did not produce results. It has been observed that a script resulting in a succesful run in another attempt may result in an unsuccesful run and vice-versa. Per event data from 1 randomly chosen ROB is requested. For larger configurations a lower rate has been observed than for smaller configurations. This is not understood. It was suggested that a too small maximum number of outstanding events could be causing this.
9. Workplan and status in relation to workplan : J. Vermeulen concluded from the present status that a number of items are late and that we may need to revise the workplan, which may need to be discussed in the next meeting.
10. Next meeting : The next meeting preferentially is tat CERN in the July trigger/DAQ/DCS week. If this is not possible a video meeting in the week before is to be organised.
11. AOB : J. Vermeulen has attended, via video, the first "Connect" (QA group) meeting on May 22 (agenda, transparancies, minutes). The different groups have reported in that meeting on procedures and tools in use. J. Vermeulen had reported that the work in the modelling group consisted of trying and testing models and that in particular comparison to paper model and measurement results are important to assess the quality of the results. R. Blair and R. Cranfield remarked that documentation of the models with UML diagrams also form a more formal approach to be used for documenting existing modelling software and as prescription for implementing new software.
J. Vermeulen, 4 June 2001