Hall D Trigger and Hall D Trigger and Data RatesData Rates

Elliott WolinElliott WolinHall D Electronics ReviewHall D Electronics Review

Jefferson LabJefferson Lab23-Jul-200323-Jul-2003

OutlineOutline

1.1. Rates from Design ReportRates from Design Report

2.2. Comparison with Comparison with LHC,CLAS…LHC,CLAS…

3.3. Additional ConsiderationsAdditional Considerations

4.4. DAQ ChallengesDAQ Challenges

1. Rates from Design 1. Rates from Design ReportReport

High trigger rate – 200 KHzHigh trigger rate – 200 KHz Deadtimeless, pipelined front endsDeadtimeless, pipelined front ends Small event size – 5 KBSmall event size – 5 KB Small Level 1 rejection rate – factor of 2Small Level 1 rejection rate – factor of 2 Modest rate off detector – 1 GB/secModest rate off detector – 1 GB/sec Modest Level 3 rejection – factor of 10Modest Level 3 rejection – factor of 10 Modest cpu needed in Level 3 – 0.1 Modest cpu needed in Level 3 – 0.1

SPECintSPECint High rate to tape – 100 MB/secHigh rate to tape – 100 MB/sec

1. Rates, con’t1. Rates, con’t

2. Comparison with LHC, 2. Comparison with LHC, CLAS…CLAS…

Compared to LHC, Hall D has:Compared to LHC, Hall D has: Similar (LHCb, BTev) or higher trigger Similar (LHCb, BTev) or higher trigger

raterate Much smaller eventsMuch smaller events Much smaller rate off detectorMuch smaller rate off detector Much smaller total trigger rejectionMuch smaller total trigger rejection Similar rate to tape Similar rate to tape Less cpu/evt needed in Level 3Less cpu/evt needed in Level 3

2. Comparison with LHC, 2. Comparison with LHC, CLAS…CLAS…

Compared to CLAS, Hall D has:Compared to CLAS, Hall D has: Much higher trigger rate Much higher trigger rate

200 KHz vs 3 KHz200 KHz vs 3 KHz Same size events Same size events

Approximately the same number channelsApproximately the same number channels Much higher rate off detector Much higher rate off detector

1 GB/s vs 25 MB/s1 GB/s vs 25 MB/s Factor 10 Level 3 rejection Factor 10 Level 3 rejection

CLAS has no Level 3CLAS has no Level 3 Factor 4 higher rate to tape Factor 4 higher rate to tape

100 MB/s vs 25 MB/s100 MB/s vs 25 MB/s

KTeV

Hall D

KTev

CLAS

Detector Rate vs Storage Rate

0

50

100

150

200

250

300

350

0 200 400 600 800 1000

Rate Off Detector (GB/s)

Ra

te t

o T

ap

e (

MB

/s)

BTev

CMS

Atlas

Hall D

KTev, CDF, DO, BaBar,

CLAS

3. Additional 3. Additional ConsiderationsConsiderations

Can not interrupt ROC every event (200 Can not interrupt ROC every event (200 KHz)KHz) Event blocking in front end cpu’sEvent blocking in front end cpu’s

Timing and trigger distributionTiming and trigger distribution Note that CLAS has:Note that CLAS has:

25 crates25 crates 1 Trigger supervisor1 Trigger supervisor 1 Event Builder and 1 Event Recorder1 Event Builder and 1 Event Recorder No Level 3 farmNo Level 3 farm

Hall D DAQ Baseline Architecture

50-100 front-end crates

Gigabit switch 200 KHz

200 Level 3 Filter Nodes

8 event builders

4 event recorders

4 tape drives

4 Gigabit switches

Network connection to silo 20 KHz

3. Additional 3. Additional Considerations, con’tConsiderations, con’t

Crates vs networked front end boards?Crates vs networked front end boards? If crates used, VME vs CPCI vs ?If crates used, VME vs CPCI vs ? (RT)Linux vs VXWorks in front end (RT)Linux vs VXWorks in front end

cpu’s?cpu’s? Need low-latency interrupt in front end Need low-latency interrupt in front end

cpu’s?cpu’s? Location of electronics, crates?Location of electronics, crates? Grounding design?Grounding design?

4. DAQ Challenges4. DAQ Challenges All problems solved somewhere, many in CLASAll problems solved somewhere, many in CLAS But new to JLab/CODA:But new to JLab/CODA:

Timing distributionTiming distribution Event blockingEvent blocking Many more front end cratesMany more front end crates Multiple event builders/recordersMultiple event builders/recorders Large Level 3 farmLarge Level 3 farm Multiple, simultaneous DAQ systems (for Multiple, simultaneous DAQ systems (for

commissioning)commissioning) Need for fault toleranceNeed for fault tolerance Integration with control systemIntegration with control system

How are we going to do it? How are we going to do it? See next talk…See next talk…

Backup slidesBackup slides

3. Comparison, con’t3. Comparison, con’tEventEvent

SizeSizeL1 L1

InputInput

RateRate

L1 L1 outputoutput

RateRate

L2 L2 outputoutput

RateRate

L3 L3 outputoutput

RateRate

KTevKTev 8 KB8 KB 100 100 KHzKHz

800 800 MB/sMB/s

20 KHz20 KHz

160 160 MB/sMB/s

2 KHz2 KHz

7 MB/s7 MB/s

CDFCDF 270 KB270 KB 50 KHz50 KHz

13 GB/s13 GB/s300Hz300Hz

80 80 MB/sMB/s

80 Hz80 Hz

23 23 MB/sMB/s

D0D0 250 KB250 KB 10 KHz10 KHz

2.5 2.5 GB/sGB/s

1 KHz1 KHz

250 250 MB/sMB/s

70 Hz70 Hz

13 13 MB/sMB/s

BaBarBaBar 33 KB33 KB

(1200 (1200 L1)L1)

2 KHz2 KHz

2.4 2.4 GB/sGB/s

NoneNone

(65 (65 MB/s)MB/s)

100 Hz100 Hz

4 MB/s4 MB/s

BTevBTev 50-80 50-80 KBKB

800 800 GB/sGB/s

80 KHz80 KHz

8 GB/s8 GB/s4 KHz4 KHz

200 200 MB/sMB/s

3. Comparison, con’t3. Comparison, con’t

EventEvent

SizeSizeL1 L1

InputInput

RateRate

L1 L1 outputoutput

RateRate

L2 L2 outputoutput

RateRate

L3 L3 outputoutput

RateRate

AtlasAtlas 1-2 MB1-2 MB 75 KHz75 KHz

100 100 GB/sGB/s

3 KHz3 KHz

5 GB/s5 GB/s200 Hz200 Hz

300 300 MB/sMB/s

CMSCMS 1 MB1 MB 100 100 KHzKHz

100 100 GB/sGB/s

100 Hz100 Hz

100 100 MB/sMB/s

CLASCLAS 6 KB6 KB 4 KHz4 KHz 4KHz4KHz

25 25 MB/sMB/s

4KHz4KHz

25 25 MB/sMB/s

Hall DHall D 5 KB5 KB 400 400 KHzKHz

200 200 KHzKHz

1 GB/s1 GB/s

nonenone 20 KHz20 KHz

100 100 MB/sMB/s