Ajit and Dario ALICE offline week 10th June Dario Favretto Ajit Kumar Mohanty ALICE Raw Data Production

Ajit and Dario ALICE offline week 10th June Production Files: Per Per Per Per2 5-81Per1 0-50Cent1 b (fm)binFile AliFastGlauber: GetRandom(bin,hard) AliFastGlauber: SetHardCrossSection(0.08) Production Files Pb+Pb Collision B=0.4T Event Class: Central Events Minimum Biased Hard Trigger

Ajit and Dario ALICE offline week 10th June General strategy For each detector we have to produce as many files as the number of LDCs that are used in the Data Challenge. Since the number of LDCs is different in each Data Challenge to avoid to redo part of the work it is convenient to define a general file structure. At the end there will be as many LDCs as the number of DDLs so it is reasonable to assume a DDL as minimal block and create the files composing the data coming from a DDL block.

Ajit and Dario ALICE offline week 10th June File Structure The number of blocks depends on: Detector Number of LDCs assigned to a particular detector Number of DDL of a particular detector TPC: 12 LDCs 36*2+36*4=216 DDLs Number of DDL block per file:216/12=18 ITS SDD: 4 LDCs 12 DDLs Number of DDL block per file: 3 ITS SPD: 2 LDCs 20 DDLs Number of DDL block per file: 10 ITS SSP: 2 LDCs 16 DDLs Number of DDL block per file: 8 MHDATA Raw Data from one DDLMini Header DDL BLOCK

Ajit and Dario ALICE offline week 10th June Mini Header The Mini Header is a fixed size block (12 bytes) that contains information on the attached data block It contains to following information (as suggested by Roberto and Fons): 1) 4 bytes Data Block size 2) 3 bytes Magic number (0x123456) used to distinguish between data and garbage. 3) 1 byte Detector 0 for TPC 1 for ITS-SPD 2 for ITS-SDD 3 for ITS-SSD.... 4) 2 bytes DDL number 5) 1 byte Flag for Compressed/Uncompressed data 6) 1 byte Mini Header Version

Ajit and Dario ALICE offline week 10th June Block rearrangement MHDATAMHDATAMHDATAMHDATA MH DATAMHDATAMHDATAMHDATAMHDATAMHDATAMHDATAMHDATA MH DATAMHDATAMHDATAMHDATA File1: File2: ITS SSD: 2 LDCs and 8 blocks per file

Ajit and Dario ALICE offline week 10th June Block rearrangement MHDATAMHDATAMHDATAMHDATA MH DATAMHDATAMHDATAMHDATAMHDATAMHDATAMHDATAMHDATA MH DATAMHDATAMHDATAMHDATA File1: File2: ITS SSD: 2LDCs and 8 blocks per file ITS SSD: 4LDCs and 4 blocks per file MHDATAMHDATAMHDATAMHDATA MH DATAMHDATAMHDATAMHDATAMHDATAMHDATAMHDATAMHDATA MH DATAMHDATAMHDATAMHDATA File3File2File1File4

Ajit and Dario ALICE offline week 10th June Data Block MHDATAMHDATAMHDATAMHDATA Data block from one DDL Uncompressed data The format of the data block depend on a particular detector and it reproduces the data as they come from the electronic ALTRO data format in case of TPC Half stave frame structure in case of ITS-SPD 32 bit word in case of ITS-SDD and ITS-SSD Since data in the simulation is not organized according to the DDL schema it has required a specific mapping for each detector. TPC mapping ITS mapping Compressed data Data is compressed using different techniques according to the detector TPC: Huffman with 5 tables ITS-SDD, ITS-SPD and ITS-SSD: Only zero suppression TPC InnerTPC Outer

Ajit and Dario ALICE offline week 10th June TPC Digits Each Pad is sampled by Time Bins For a given Pad: Signals Bunch Length Time Bins (Time Gap)

Ajit and Dario ALICE offline week 10th June ALTRO format K 60k 40k 20k 10k OH (%) T (%) BL (%) Sample (%) Size (Mb) Multiplicity S0S1S2S3 S4TBBLS5 TB BLS6S7 S10TBBL2AA S8S9TBBL Words # Pad # Row # Sec # S18S19S20S21 S11TBBLS12 BL2AA S13S14TBBL Words # Pad # Row # Sec # S15S16S17TB... TRAILER 10 bits words Pad n Pad n+1

Ajit and Dario ALICE offline week 10th June Huffman Compression 5 Frequency Tables are used -Bunch Length -Time Gap -Isolated Samples -Border Samples -Central Samples Ref: Compression of TPC data in the ALICE experiment A.Nicolaucig, M. Mattavelli, S. Carrato ALICE-PUB version 1.0

Ajit and Dario ALICE offline week 10th June Optimized Huffman Table Per3 Best Per2 Formulae Per2 Best Per2 Formulae Per5 Best Per2 Formulae Per1 Best Per2 Formulae Per4 Best Formulae Cent1 Best Per2 Formulae Comp(%)FileComp(%)File Ref 1: ''Existence of Dynamical Scaling in the Temporal Signal of Time Projection Chamber'' A. K. Mohanty, D. Favretto, F. Carminati and K. Safarik. ALICE NOTE 2003 Ref 2: ''Optimization of frequency tables for static Huffman compression of ALTRO raw data'' D. Favretto, A. K. Mohanty, F. Carminati and K. Safarik ALICE NOTE 2003

Ajit and Dario ALICE offline week 10th June Raw Data Volume (MB) TPCslice TPCslice TPCslice TPCslice TPCslice TPCslice TPCslice Total (37.9) Compression 51.2% (TPC Central Event)

Ajit and Dario ALICE offline week 10th June ITS-SPD Silicon pixel detector is composed by 120 half stave module One half stave is composed by two modules (as they are called in the simulation) and in each module there are five chips. Each chip is represented by a matrix of 256*32 elements Half Stave

Ajit and Dario ALICE offline week 10th June ITS-SPD data format Pixel hit 0Chip header 2 Chip trailer 2Pixel fill word Pixel hit nPixel hit n-1 Chip trailer 1Pixel hit n Pixel hit 2Pixel hit 1 Chip trailer 0Chip header 0 Pixel hit 0 Pixel hit 2Pixel hit 1 Chip header 1 Chip trailer 9Pixel hit n Pixel hit 0Chip header 2 Pixel hit 0Chip header 3 Pixel hit 2Pixel hit 1 Half Stave Frame Chip hit count Chip Trailer Chip addr 011XX Half stave # Chip Header 10XColumnRow Pixel hit 110x3EDC Pixel fill word Ref.: A. Kluge 15 Nov 2000 Every 16 bits word has a unique prefix !

Ajit and Dario ALICE offline week 10th June ITS-SDD/SSD data format 32 bits words are used to describe the digits format of Silicon Drift and Silicon Strip Detector Module IDAnode NumberTime bucketADC Value ITS SDD digits format: Module ID N/P Strip NumberADC Value ITS SSD digits format: ADC cha.Strip NumberADC ValueADC mod.PEX

Ajit and Dario ALICE offline week 10th June Raw Data Volume (MB) SPDslice SSDslice SPDslice SSDslice Total (0.24) Total 0.47 (0.20) SDDslice SDDslice SDDslice SDDslice Total 2.47 (1.5) ITS central Event

Ajit and Dario ALICE offline week 10th June How to generate Raw Data TPC Create galice.root Create digits AliTPCHits2Digits.C Create DDL mapping AliTPCDDL.C(''galice.root'') Execute AliTPCDDLRawData.C ITS Create galice.root Create digits AliITSHits2Digits.C Execute AliITSDDLRawData.C Ref: ''Production of Compressed and Uncompressed Raw Data for ALICE Data Challenge'' D. Favretto, A. K. Mohanty

Ajit and Dario ALICE offline week 10th June DAQ System Mass Storage System DATE FORMAT Online analysis modules

Ajit and Dario ALICE offline week 10th June DATE Format Event HSubEvent HPAYLOADSubEvent HPAYLOAD Raw Data from 1 LDC PAYLOAD structure in case of CALIBRATION or PHYSICS Event: MHDATAMHDATAMHDATA PAYLOAD Equip. H MHDATAMHDATA PAYLOAD Equip. H PAYLOAD structure in all the other types of Event: This format can be simulated by raw2date program

Ajit and Dario ALICE offline week 10th June To Do Detectors interface TPCRawData2Cluster (Thomas has succesed) ITSRawData2Cluster (To be implemented) Online tools ITS vertex multiplicity TPC noise monitoring ITS-TPC tracking Plus more AliMDC AliEn Interface

Ajit and Dario ALICE offline week 10th June Silicon Pixel Detector DDL number modules 0 { 0, 1, 4, 5, 80, 81, 84, 85, 88, 89, 92, 93}, 1 { 2, 3, 6, 7, 82, 83, 86, 87, 90, 91, 94, 95}, 2 { 8, 9,12,13, 96, 97,100,101,104,105,108,109}, 3 {10,11,14,15, 98, 99,102,103,106,107,110,111}, 4 {16,17,20,21,112,113,116,117,120,121,124,125}, 5 {18,19,22,23,114,115,118,119,122,123,126,127}, 6 {24,25,28,29,128,129,132,133,136,137,140,141}, 7 {26,27,30,31,130,131,134,135,138,139,142,143}, 8 {32,33,36,37,144,145,148,149,152,153,156,157}, 9 {34,35,38,39,146,147,150,151,154,155,158,159}, 10 {40,41,44,45,160,161,164,165,168,169,172,173}, 11 {42,43,46,47,162,163,166,167,170,171,174,175}, 12 {48,47,50,51,176,177,180,181,184,185,188,189}, 13 {50,51,54,55,178,179,182,183,186,187,190,191}, 14 {56,57,60,61,192,193,196,197,200,201,204,205}, 15 {58,59,62,63,194,195,198,199,202,203,206,207}, 16 {64,65,68,69,208,209,212,213,216,217,220,221}, 17 {66,67,70,71,210,211,214,215,218,219,222,223}, 18 {72,73,76,77,224,225,228,229,232,233,236,237}, 19 {74,75,78,79,226,227,230,231,234,235,238,239} ITS Mapping 2198 Modules ! CLOSE

Ajit and Dario ALICE offline week 10th June TPC Mapping CLOSE