PCIe40 — a Tell40 implementation on PCIexpress Beat Jost DAQ Mini Workshop 27 May 2013

Beat Jost, Cern PCIe40 Features ❏ The PCIe40 is functionally identical to the AMC40, BUT implemented in a PCIexpress form factor and without discrete output path  data go out on the PCIexpress path into the host PC ❏ Hardware almost identical (same FPGA, same input connectors) ❏ PROs: ➢ Infinite buffering, as the PC memory is the event-buffer  without additional ICs ➢ Freedom of choice for the network technology to-be-used downstream ➥ Eventually almost for free, i.e. on-board/chip ➢ PCIe-3 sufficient (100 Gb/s). Usually PCIe is backward-compatible ➢ IPMI etc. is part of the host infrastructure. ❏ Cons: ➢ Need a PC as host (holder of the cards) ➥ However we do not rely on many PCIe slots per machine. ➢ Need a separate plug for the TFC signals (single fibre pair) ➢ Possibly quite some firmware effort to offload host for PCIe transfers 2 DAQ Mini Workshop, 27 May 2013

Beat Jost, Cern A “physical” view of the PCIe40 ❏ Minimal variant – no external memories / no transmitters for GBT ❏ Power up to 75W (use graphics cards standard) ❏ PEX8733 can be replaced by PCIe x 16 softcore TELL40e 3

Beat Jost, Cern Usage ❏ The PCIe40 cards will be housed in server PCs (~500 units) ❏ These PCs would be integrated in an event-building network, i.e. each server acts as data receiver of its PCIe40 card via PCIe and receiver of corresponding MEPs from the (N-1) other servers. Destination address originates from the TFC system, just as now… ❏ Once events are built, additional processing on full events could be envisaged, e.g. LLT or some form of HLT0 to reduce rate, if needed. ➢ Prob. some 60% of the CPU power of still available (TBT) ❏ Subsequently, the data are transferred to the HLT farm for software triggering 4 DAQ Mini Workshop, 27 May 2013

Beat Jost, Cern Pictorially 5 DAQ Mini Workshop, 27 May 2013 PC PCIe40 24 GBT TFC Event Building Switch PC PCIe40 24 GBT TFC … HLT Farm MEP Event ~500 units

Beat Jost, Cern Conclusion ❏ We believe that the PROs outweigh the CONs ❏ A conceptual study of the board and of the system is clearly worth doing ➢ A prototype or 2 would be nice… ❏ Overall costing studies necessary 6 DAQ Mini Workshop, 27 May 2013