STT session at L2 workshop

Friday, 24 April, 13:30 to 15:30

Agenda:

  1. STT baseline design vs STT with SLIC/FIC --- performance comparison [Ulrich Heintz] (15 min.)
  2. Cost and engineering impact of L2 options on STT [Hal Evans] (15 min.)
  3. status report on track fitting algorithm implementation, STT baseline processor card [John Hobbs] (15 min.)
  4. status report on queueing studies [Terry Heuring]
  5. impact of possible L1CFT changes (Glink to Cypress) on STT [Marvin Johnson] (5 min.)
  6. define and agree on criteria for decision on STT options (discussion, decision?) (20 min.)


  1. Requirements for STTpp, and performance comparison: STT baseline design vs STT with FIC/SLIC/Alpha [Ulrich Heintz] Ulrich showed the list of requirements for the STTpp, an updated version of that shown in the meeting of April 7; for comparison baseline vs SLIC/..…, see see here for timing comparison, and here for general comparison -- pros and cons. It appears that possible engineering amd maintenance benefits of the FIC/SLIC option are outweighed by less performance. Note that some of the numbers quoted in the timing comparison need to be checked, in particular the processing times for the track fitting; more reliable numbers will be available once John Hobbs has finished his< algorithm and timing studies.

  2. Cost and engineering impact of L2 options on STT [Hal Evans]
    This is a comparison of various options for realizing the TFC with standard L2 boards, only with regards to cost and engineering needs, without consideration of feasibility or performance. In all options it is assumed that the baseline STC (with slight modifications depending on the option) is used. Among the options considered, only the the ones with the classic or the standalone SLIC has an advantage in the form of less engineering, while all the other options have no engineering advantage and higher cost. Transparencies of Hal's presentation are available here

  3. Track fitting algorithms, TFC [John Hobbs] John Hobbs is continuing his studies in search of the optimal track fitting algorithm, as well as various implementation options (DSP's, Altera FPGA's, other PLD's)

  4. queueing studies [Terry Heuring] Terry Heuring is doing STT studies using the RESQ package; no results yet.

  5. Impact of possible L1CFT changes (Glink to Cypress) on STT [Marvin Johnson] Marvin is against slowing down read-out -- advocates keeping G-link for SVX read-out and L1CFT.

  6. Main decisions affecting the STT taken at the L2 workshop: