1 / 14

BNet: further investigations

BNet: further investigations. • • • •. n. H. Currently investigated structure. n=4 : 16x16. n * (n - 1) / 2 bidirectional connections. TG/BC. n - 1 ports. n - 1 ports. BNet controller. switch n × n. switch n × n. • • • •. n. • • •. n - 1. H: histogrammer TG: event tagger

minna
Download Presentation

BNet: further investigations

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. BNet: further investigations Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  2. • • • • n H Currently investigated structure n=4 : 16x16 n * (n - 1) / 2 bidirectional connections TG/BC n - 1 ports n - 1 ports BNet controller switch n × n switch n × n • • • • n • • • n - 1 H: histogrammer TG: event tagger HC: histogram collector BC: scheduler DD: data dispatcher ED: event dispatcher DD/ED DD/HC DD/ED active buffer CNet CNet PNet CNet PNet Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  3. Simulation with SystemC Modules: • event generator • data dispatcher (sender) • histogram collector • tag generator • BNet controller (schedule) • event dispatcher (receiver) • transmitter (data rate, latency) • switches (buffer capacity, max. # of package queue, 4K) Running with 10 switches and 100 end nodes. Simulation takes 1.5 *105 times longer than simulated time. Various statistics (traffic, network load, etc.) Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  4. Some statistic examples single buffers excluded! Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  5. Scheduling strategy • use data channels for meta data • traffic shaping by schedule • calculate schedule in advance • data transfers are triggered at absolut times • requires deterministic behavior of network • delivery control by buffer monitoring • no transfer acknowledge Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  6. Factorisation of 32x32 switch 2 layers of 6 6x6 switches 6-1 6-2 6-3 6-4 6-5 6-6 1-1 1-2 1-3 1-4 1-5 1-6 • • • • 6-1 6-2 6-3 6-4 6-5 6-6 1-1 1-2 1-3 1-4 1-5 1-6 Variance in latency increases! Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  7. Factorisation of 32x32 switch factorized switch 1 factorized switch 2 1 switch 4 switches 2 switches Variance in latency increases! Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  8. Synchronization of senders • Extra time clock distribution (~µs) • or from concentrator (must then be synchronized) The active buffers must have a common clock to start transfers at a given absolut time. Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  9. Broadcast problematic • Broadcast through factorized switches • How to guarantee packet delivery? Broadcast is needed to distribute event tags and schedule start time to all data dispatchers. Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  10. Error detection • How to ensure that all data arrived? • How to recover if not? • Recover from component fail (or removal)? • When emergency? BNet controller gets buffer status from all DD/EDs. These are sent according schedule. Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  11. Network performance measurements IXIA testbed components chassis IXIA 1600T 10 GE load module (traffic generator/analyzer) Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  12. Network performance measurements TALLY: measurement of Force10 E1200 Point to point Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  13. Topics for investigations • Event shaping • Separate meta data transfer system • Addressing/routing schemes • Broadcast • Synchronization • Determinism • Fault tolerance • Real test bed Hans G. Essel, Sergey Linev: CBM - DAQ BNet

  14. Hans G. Essel, Sergey Linev: CBM - DAQ BNet

More Related