1. Offline Report Outline: Status update DST Proposal P. de Simone
24 September 2001
Outline:
Status update
DST Proposal

2. Processing of summer 2001 data
Reference data set:
Runs (1 June - 19 Sep)
7.6 G triggers
Offline L dt = 58.3 pb-1
DBV-9 : 17.0 pb-1
DBV-10: 41.3 pb-1
Total events collected:
326.7 M Bhabhas
125 M f decays
est. sf = 2.9 mb
28.4 M KL tags
21.7 M KL crash
50.7 M K+K- tags
15.7 M rp tags
6 Sept
1 June
51 pb-1
7.3 pb-1
LAB integrated luminosity

3. Event streaming cos raw bha kpm ÷10 ksl rpi rad clb ÷100 flt afl
2000 Hz
cos
40 Hz
raw
DC recon.
Evt. Class
bha
86 Hz
prescaled
cosmic
kpm
÷10
ksl
1640 Hz
yes
590 Hz
EmC
recon. MB
cosmic
Bhabha
DC recon.
Evt. Class
rpi
70 Hz
rad
yes
clb
÷100
flt
700 Hz
afl
9 Hz

4. Processing statistics for summer 2001 data
Raw data: 7565 M Events, 20 TB
Physics: 3.0 % of total events
34 % of raw volume
Bhabhas: 4.0 % of total events
25 % of raw volume
20 ms
60 ms
Stream Events (M) Volume (GB) Summary
kpm
ksl
rpi M Events
rad TB
clb
bha
flt
afl M Events
cos TB
Avg. fraction of events tracked 36%
NOTE : the new IBM machines halve the reconstruction time
NOTE : in 2000 the avg. fraction of tracked events was 26 %

5. datarec performance in summer 2001
Daily averages
— Acquisition rate (evts./day) — Reconstruction rate (rec. evts./day)
Follow-up
End of data
Start of rec. at 6 p.m.  Avg. rec. rate on 64 CPU’s 3KHz
Troubles managing more CPU’s
Avg. reconstruction rate on 64 IBM CPU’s : 1.5 KHz
Staging and procedural losses count
Once in stable situation, able to follow
the present DAQ rate

6. datarec executables DBV-9 and DBV-10
DCONVR Added fine parametrizations of the resolution curves obtained using data
VTXFIN Minor bugs fixed
DBV - 10:
A_C zlib event compression
physics streams 160 GB/pb-1  86 GB/pb-1
TRCLMOD The talk-to defaults have been changed. By default, track-to-cluster association
for tracks connected to a vertex at the far end is now performed
ECLMOD The b cut window defining the KL crash tag has been widened

7. datarec platform dependence
Test of DBV-10 on SunOS and AIX performed in July:
Input: 1000 raw events (Run 18850)
Output in ksl stream:
AIX: 11 events, including 3 not found on SunOS
SunOS: 10 events, including 2 not found on AIX
Limited information from quick diagnostics  potentially misleading statements
Differences appear at track-fit level
Differences became more pronounced after DBV-8
Differences made worse by discreteness in fine s-t error parameterizations
Elements of truth in these statements, but full story is more complicated
Turn attention to impact on analysis

8. Platform dependence: stream contents
Run (4.8 Mtrig) processed on AIX/SunOS
Detail for ksl stream:
Only AIX: 6239
Only SunOS: 3688
Different length:
Otherwise equal:
After KL tag analysis:
Rxy < 5 cm, |z| < 20 cm
|Mpp – MK| < 20 MeV
One track assoc. to clust.
Difference in counts: 0.04%
(AIX/SunOS: 22731/22722)
Difference in events: 0.24%
(Only AIX/SunOS: 32/23)
Stream/Tag
AIX
SunOS
Diff (%)
kpm
42516
42536
0.05
w/vertex
9960
9969
0.09
ksl
119354
116812
2.1
KSTAG
72737
70083
3.6
KSNEUT
10121
10129
0.08
KLCRASH
20419
20429
KLTAG (Gold)
24757
24759
0.01
INTER
5551
5445
1.9
rpi
13842
13844
rad
34099
34088
0.03
ppg
1789

9. Platform dependence: Monte Carlo
MC sample: 1000 ksckl2pc events (KS  p+p-, KL  p+p-)
43 events with different length
1 event with different event-type tag
Gold KLTAG, KLCRASH, KSEMIL on both
INTER on AIX only
1 event with different stream tag
Gold KLTAG, KSEMIL, INTER on Sun
Lost (UFO) on AIX
Platform comparison using MC has subtle points:
In MC, DTCE is generated on one platform, reconstructed on both
When data analyzed in same way, fewer differences observed
Statistics are very poor
Effects appear to be at per-mil level in MC, as in data
SunOS
disp. vtx.
split
AIX

10. Platform dependence: Observations
Large differences apparent at a glance are characteristic of events that are:
Poorly reconstructed
Intrinsically difficult to reconstruct
Background
Much smaller differences in event samples of physics interest
Fractional differences between platforms at per-mil level
We regularly tolerate such differences when starting datarec without waiting for calibrations
Much work in progress
Still trying to understand the problem
Situation less alarming than initially feared

11. New information in DB2
Counters: VLAB, Gold Bhabha, gg, KSp+p-, KSp0p0, KL crash
20 fields K+K-, rp, Neutral Radiative, Rejected Bhabha, cosmic, MB
Job table +8 unused fields
Fitted quantities: s from Bhabhas, Etot from gg, T-L/c from Bhabhas, T-L/c from gg,
20 fields M(KSp+p-), sM(KSp+p-), P(KS)
Job table +13 unused fields
Status flags: Biases: Indicates any reconstruction errors that cause biases in stream
2 flags per stream Obsolete: Indicates if file has been superseded by a new reconstruction
datarec file table
Encoding of status flags:
Word of bits independently set to indicate reasons for bias/motive for reprocessing
Calibrations (DC, EmC t, EmC E)
Bugs (FILFO, clustering, tracking, each ECL filter, etc.)
No bits set means stream good to use for analysis
Example KID query:
input url "dbdatarec:stream_code=’rad’ and run_nr between and 17330
and Biases=0 and Obsolete=0"

12. Proposal for mini-DST production
Mini-DST’s to be produced:
in dedicated production pass
in zlib-compressed YBOS format
with a bank subset essential for physics analysis, including summary banks
for different event classification substreams
it looks reasonable to reach 5-6 KB/evt
Status:
zlib compression Done
Scripts Some work needed
Retained banks Proposal exists and
Summary banks needs approval
Substreaming from analysis groups
15 October is the target date for the readiness of a preliminary version of the
DST production mechanism

13. DST substreams proposal
Proposal based on ksl Ntuple, radiant substreams, datarec streams, and EVCL tags
ks2pi KS  p+p-, KS  p0p0
ksemil KS semileptonic decays
klcr KL crash
kl2p0 KL  p0p0
kl3p0 KL  p0p0p0
klppp KL  p+p-p0
intertag interferometry tags
kpm kpm (K+K-) stream
rpi rpi (rp) stream
neu_max4g neutral events, at most 4 prompt g’s
neu_min5g neutral events, at least 5 prompt g’s
cha_min3g 2 tracks, 3 or more prompt g’s
cha_ppg p+p-g tagged events
clb clb (m+m-, p+p-) stream

14. DST banklist proposal Raw Banks LRID, EVCL T0GL
2 KB/evt w/w/o compression
LRID, EVCL
Event headers
T0GL
Global t0
TRIG (TPIE, TMON, TCAF, MOKA)
Trigger summary
Based on Ntuple block, to be done
CTRG
Sector-to-cluster
CSPS
Calorimeter hits
Summarizes CELE+CWRK, almost done
CLUS
Calorimeter clusters
Summarizes CLPS+CLLS, almost done
QWRK
QCAL hits
DC hit counts
Based on Ntuple, to be done
DTFS
Fitted tracks
DST version without hit lists
DVFS
Fitted vertices
TCLO
Track-to-cluster
ECLS, ECLO
Event classification
Only highest-numbered version in DST
KNVO, VNVO, INVO
Neutral vertices