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Aleph computing after 2000Aleph computing after 2000

FalconFalcon

LinuxLinux

shift50shift50

Access to dataAccess to data

Marco Cattaneo, Aleph plenary in Siena, 1st October 1999

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Plans for Falcon (and ALWS)Plans for Falcon (and ALWS)

Data-taking ends 9/2000Data-taking ends 9/2000 Reprocessing of 2000 data possible well before Xmas

Complete reprocessing of LEP II data?Complete reprocessing of LEP II data? Falcon will be kept in Echenevex until 12/2001

From 2002, keep in building 2:From 2002, keep in building 2: at least one machine running VMS

ALNEWS - unless we find and alternative connected to at least one DLT drive

Access to (small quantities of) raw data

How long do we want (VMS) access to raw data?How long do we want (VMS) access to raw data? Do we archive it? How (copy to different format)? Where?

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LEP II reprocessingLEP II reprocessing Falcon at full speed: 10pbFalcon at full speed: 10pb-1-1 per day per day

Integrated luminosities1996 1997 1998 1999 2000 Total

21.5 68.2 182.7 192+50? 200? ~700 pb-1

(on 27/9)

Will take ~3 months for the dataWill take ~3 months for the data Assumes all calibrations / alignment ready on time Assumes no mistakes

Neither was true for LEP I reprocessing.... MonteCarlo took much longer....

I think we cannot start any later than spring 2001I think we cannot start any later than spring 2001 Decision by September 2000 Test with 2000 end of year reprocessing? Then work backwards through the years

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An aside:An aside:

In 1999 we will have collected ~240pbIn 1999 we will have collected ~240pb-1-1

Run ends 7th November Xmas shutdown from 18th December 24 days needed to reprocess

Latest possible start is 24Latest possible start is 24thth November November

Aim for:Aim for: Reprocessing of Z0’s on weekend of 13th November

5 days of checks, then: Start reprocessing of high energy on weekend of 20th

November

This is very tight! This is very tight! Must start now to assemble the pieces....

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Linux supportLinux support

Many labs have (or plan) large Linux facilitiesMany labs have (or plan) large Linux facilities e.g. IN2P3, RAL, Pisa, Glasgow, Lancaster, NBI, ... e.g. CERN:

LXPLUS (interactive) service since June, 3*shift50 by November LXBATCH 4*shift50 from

November PCSF (currently WNT, largely Linux in 2000) up to 5*(HP)CSF

Aleph will have in 2000: roughly equal quotas on CSF and “Linux PCSF” (insufficient

capacity on CSF to satisfy requests of the 4 LEP experiments) “sizeable” quota on LXBATCH

Aleph software already runs on LinuxAleph software already runs on Linux Thanks to Anders Waananen and the NBI team Extensive checks by David Smith and Stephane Jezequel

some minor precision-related differences

KINGAL is missing

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Linux support proposalLinux support proposal

Clearly we must support Linux officially in AlephClearly we must support Linux officially in Aleph Before end of year for everything already ported For most used generators

Other generators on request

Can Aleph support 4 Operating Systems at Can Aleph support 4 Operating Systems at CERN?CERN?

Everything is possible, but: HP OS frozen at HPUX10 No new HP investment at CERN, future of CSF unclear

DROP official HPUX support at end 2000DROP official HPUX support at end 2000 One year overlap with Linux support Interested institute(s) could take over support

c.f. NBI for Linux

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What about Digital Unix?What about Digital Unix?

SHIFT50: SHIFT50: Support and maintenance is currently approved until end

2002 ALEPH will request to extend this to end 2003 if we reprocess

Aloha (and the homelabs)Aloha (and the homelabs) Huge investment, and huge capacity on aloha

However: However: CERN/IT proposal to “minimise RISC” by end 2001

Freeze OS support to DUX 4.0F (probably obsolete end 2001) What about Aleph analysis after 2002/2003?

So:So: We MUST support DUX until end of major analyses We SHOULD discourage further investment in DUX hardware 2002/2003 could be tough (in particular for shift50)

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Shift50, the final actShift50, the final act

It COULD be that, earlier than 2003:It COULD be that, earlier than 2003: SHIFT50 will be small fraction of CPU used by Aleph The majority of analyses will have shifted to Linux The maintenance of SHIFT50 has become problematic

If all of the above, we could imagine If all of the above, we could imagine switching off shift50 BEFORE end of 2002switching off shift50 BEFORE end of 2002

Of course, disks would be mounted elsewhere

This is decoupled from any decision for This is decoupled from any decision for aloha and DUX supportaloha and DUX support

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And after 2002/2003?And after 2002/2003?

Encourage migration away from DUX A.S.A.P.Encourage migration away from DUX A.S.A.P. Make Aleph environment “independent” of shift50

Move scratch areas, EDIRs and user workspace to AFS Continue to access ntuples via RFIO from shift50 /wg disks (more

efficient than AFS) Stage pool is already accessible from any authorised CERN client

Take advantage of huge public Linux capacity coming online Make available Aleph Linux customisation for desktop PCs With a little gentle pushing, physics analysis will follow CPU...

Transparent continuation of analyses after 2003Transparent continuation of analyses after 2003 Can continue on CERN public batch (hopefully Linux....) Can switch off SHIFT50 without side-effects Can drop support for DUX without side-effects

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But what about the data?But what about the data?

EPIO/BOS not supported outside AlephEPIO/BOS not supported outside Aleph

Tape media become rapidly obsolete:Tape media become rapidly obsolete: 1995: move from 3480 to DLT 2000 1998: move from DLT 2000 to STK Redwood

3480 no longer available at CERN

2000: STK Redwood discouraged, use STK 9840No DLT 2000 robot, rare manual mounts

possible

2003: ?

Do we want to archive our data?Do we want to archive our data? What (MINI/DST/POT, which MC) How? (Copy to next generation tape? OO database?) What about analysis tools?

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Data Analysis toolsData Analysis tools ALPHA++ALPHA++

A first version for doing “real” user analysis is available for tests!

M.Hörndl (summer student) has shown that it is possible to perform a QCD analysis

(however, for the moment only small statistics) Everybody interested should

Look at the Web pagehttp://alephwww.cern.ch/~disserto/objty/Welcome.html( Aleph home page -> Offline system -> ALPHA++ )

Contact G.Dissertori

New SCANBOOK implementation New SCANBOOK implementation (A.Bonissent, F.Loverre, (A.Bonissent, F.Loverre, J.Boucrot)J.Boucrot)

JAVA client accessing ORACLE database at CERN Light client, single database copy, easier maintenance, better

performance over network Available for testing now.

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DISCUSSIONDISCUSSION

Last reasonable date for LEPII reprocessing?Last reasonable date for LEPII reprocessing?

How long do we need/want access to raw data?How long do we need/want access to raw data? And ALNEWS?

Support Linux now? Drop HP support end 2000?Support Linux now? Drop HP support end 2000?

Are long term plans for DUX/shift50 reasonable?Are long term plans for DUX/shift50 reasonable?

Should we worry about archiving the data?Should we worry about archiving the data?