„the square root of serving multiple experiments is a single dcache“
DESCRIPTION
GridKa dCache. LHCb. CMS. compass. cdf. ALICE. dteam. belle. auger. ops. ATLAS dCache. ATLAS. ops. c3grid. astrogrid. medigrid. ingrid. kerndgrid. textgrid. wisent. hepcg. Deadlock situation One dteam file located on ATLAS pool PNFS id not known to dCache - PowerPoint PPT PresentationTRANSCRIPT
„The square root of serving multiple experiments is a single dCache“
GridKa dCache
CMS ATLAS ALICE LHCb
hepcg wisent textgrid kerndgrid ingrid
astrogridmedigrid
c3grid
9 other D-Grid VOs
com-pass
cdf auger belle ops dteam
D-Grid dCache
c3grid
astrogrid
medigrid
kerndgrid
ingrid
textgrid
wisent
hepcg
GridKa dCacheLHCb CMS compass
ops
cdf
belledteam
auger
ALICE
ATLAS dCacheATLAS ops
Procedure1. Pool migration (hosts only serving ATLAS pools)
2. Installation of new ATLAS administration nodes
3. Complete downtime of original dCache instance
a) dump of SRM and PNFS DB
b) Remove ATLAS configuration:
i. Switch off all ATLAS pools
ii. PoolManager
iii. Pin- and SpaceManager entries
iv. PNFS DBs
c) Restart original dCache instance
4. Reload DB dumps in new ATLAS instance
a) Remove all non ATLAS entries from DBs
b) Change dCacheSetup on all ATLAS pools
5. Start ATLAS instance
Deadlock situation One dteam file located on ATLAS pool PNFS id not known to dCache Pool tried flushing file to tape PnfsManager did not know file PnfsManager run in deadlock situation
[email protected] Centre for Computing
Motivation Performance problems – bottleneck SRM, PNFS
Further single points of failure: PoolManager, PinManager
Easier to manage due to less complex configuration
VOs do not disturb each other
Configuration can be fine tuned for the requirements of the separated VO
Further information today:
037 - Improving data distribution on disk pools for dCache
070 - dCache administration at the GridKa Tier-1-center, ready for data taking
069 - Reference installation for the German grid Initiative D-Grid
ATLAS nodes
Head node
PNFS deamon, PnfsManager, postgres DB
SRM,utilityDomain, postgres DB
gPlazma
Billing DB
dCap door
4 gridftp doors
23 pool nodes
Forschungszentrum Karlsruhe GmbH
Hermann-von-Helmholz-Platz 1
D-76344 Eggenstein-Leopoldshafen
D.Ressmann, S.Halstenberg, C.Jung, A.Trunov, J.van Wezel
Separation
9 other D-Grid VOs