FLP data flow – FLP prototype

Filippo Costa

ALICE O2

9th June 2015 WUHAN, CHINA

2

Outline

• Theory:– FLP data flow.

• Practice:– FLP prototype

June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

3June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

Theory

4June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

Data flow

FEE data

FLP – EPN data flow

5June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

FLP data flow

6June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

• Data are produced by the detectors in continuous or triggered read-out

mode, synchronized by the trigger system.

• A mixture of readout links will be used:– DDL1 running @ 2.125 Gb/s– DDL2 running @ max 6 Gb/s– GBT running @ 3.2 / 3.52 / 4.48 Gb/s

• For the continuous detector the data stream is split into data frames

using a reference trigger called heartBeat signal. The frames are

accumulated over a period of 20 ms.

FEE data flow

7June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

• Several streams are aggregated and buffered in the memory of the FLP.

These nodes perform a data reduction and compression of about 2.5

• The FLPs produce a Sub-Time Frame (STF) that could be empty for the

FLP receiving data from triggered detectors that didn’t receive triggers

during that period of time

FLP data flow

8June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

• The STFs are then dispatched to the Event Processing Nodes (EPNs) for

aggregation.

• All the STFs related to the same time period are sent to one EPN.

• The EPN communicates to the FLP its availability to receive data, so a

proper load balanced list of EPNs can be prepared and used by the

FLPs.

FLP - EPN data flow

9June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

Time Frame

10June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

Time Frame

11June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

Time Frame• The Data flow and processing will be

based on the concept of Time Frame,

all the data blocks will need to have a

clear time identifiers

12June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

Time Frame descriptor• The data granularity in Run3 is driven by the heartbeat (HB) signal, that

is triggered at equal time intervals, on some bunch crossing ID. The time

range is about 20 ms

• All the input data blocks acquired in a HB interval are assigned to a

single Time Frame descriptor tag

13June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

Time Frame descriptor

14June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

FLP data aggregration

15June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

Practice

16June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

Schedule

• MILESTONE: – ITS half-layer test beginning 2017

17June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

FLP structure

Infrastructure and

services

• CCM

• Logging

• Logbook

• DQM

• …

18June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

FLP requirements

• Collect data from a card plugged in an FLP machine

and output sub Time Frames to be used by data

reduction processes via ALFA.

• Processes must be controlled centrally.

• Run conditions must be logged.

• Data must be monitored.

19June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

FLP software environment

• This section is covered by  B. Von Haller – Tools and software process for the FLP prototype

20June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

FLP hardware environment

21June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

FLP prototype

22June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

3 … 2 … 1 -> START

23June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

What do we have?

• Hardware:– FLP prototype– C-RORC (CRU style)– Plan B : AMC 40 board

• Software:– Everything listed before will be installed in the machine.

• Time:– Not a lot, but we already started working on the issue as much as we can.

• Coffee:– Plenty of it

• Brain:– Plugged in and working 100%

24June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

Thank you

25June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

References

The GBT Project Home Page: https://espace.cern.ch/GBT-Project

The GBTx ASIC User Guide https://espace.cern.ch/GBT-Project/GBTX/Manuals/gbtxManual.pdf

The GBT-FPGA Project Home Page https://espace.cern.ch/GBT-Project/GBT-FPGA

The GBT_FPGA: one unified core for multiple users, ppt, M. Barros Marin, Feb 2014 https://svnweb.cern.ch/cern/wsvn/ph-ese/be/gbt_fpga/tags/doc/GBT-FPGA_students-fellows_ManoelBarrosMarin_2014_02_05.pdf

The GBT_FPGA project, M. Barros Marin, S. Baron, ACES 2014 https://svnweb.cern.ch/cern/wsvn/ph-ese/be/gbt_fpga/tags/doc/gbt_fpga_aces2014_poster.pdf The GBT encoding scheme: “An Error-Correcting Line Coding ASIC for a HEP Rad-Hard Multi-GigaBit Optical Link”, G. Papotti, Proc. 2nd Conference on Ph.D. Research in Microelectronics and Electronics (PRIME 2006), Otranto (Lecce), Italy, 12-15 June 2006, pp.225-8.

The GBT-FPGA Core: Features and Challenges, M. Barros Marin et al., 2015 JINST 7 P01075.

26June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

References

ALICE DDL1/DDL2 protocolhttp://alice-proj-ddl.web.cern.ch/alice-proj-ddl/

DDL, the ALICE Data Transmission Protocol and its Evolution from 2 to 6 Gb/s.https://inspirehep.net/record/1359148

Or

Write an email : Filippo.costa at cern.ch

27June, 9 2015 - 5th Workshop on ALICE ITS, MFT and O2 | Wuhan, CHINA

References

ALICE DDL1/DDL2 protocolhttp://alice-proj-ddl.web.cern.ch/alice-proj-ddl/

DDL, the ALICE Data Transmission Protocol and its Evolution from 2 to 6 Gb/s.https://inspirehep.net/record/1359148

Or

Write an email : Filippo.costa at cern.ch