Host site location model in STAR

One of the aspects about MAGDA integration is to fit the host-site-location scheme as defined in MAGDA.

Background

In MAGDA, an host is a machine or a group of machines. A site is a host plus a protocol on how to access data. A location is a path leading to a directory managed by MAGDA. A file in magda is identified by something like a URI, but slightly different. A URI, in fact, would be:

protocol://host/path/filename
protocol:/path/filename

while MAGDA has:

site:/path/filename

A host can span from a single machine (atlastw.phy.bnl.gov - Wenaus laptop) to a much bigger entity (atlas.cern.ch - CERN ATLAS). A site tells how you access a host. For example, through AFS (cernatlasafs - AFS site for atlas.cern.ch host) or HPSS (cernhpss - HPSS site for atlas.cern.ch host).

Proposal for STAR

We can divide STAR in the following hosts:

• star.bnl.gov - STAR at BNL
• star.lbl.gov - STAR at Berkley
• star.xxxx.yyy - STAR at a different institution

Now we analyze the BNL host. The other hosts will be similar

• starrcfnfs - The NFS space available at RCF.
• starafs - The AFS space available at RCF.
• starrcfhpss -The HPSS space available at RCF.
• starrcfrcas - The local disks available on the RCAS farm at RCF.

For these sites, we can define locations, such as:

• starrcfhpss:/home/starreco/reco/ - prime location for STAR reconstructed data (corresponds to /home/starreco/reco/ directory in HPSS at BNL)
• starrcfnfs:/star/data15/reco/ - a replica location for STAR reconstructed data on NFS (corresponds to /star/data15/reco/ directory on NFS at BNL)
• starrcfnfs:/star/data21/reco/ - another replica location for STAR reconstructed data (corresponds to /star/data21/reco/ directory on NFS at BNL)
• starrcfrcas:/rcas6080/home/starreco/reco/ - a replica location for STAR reconstructed data, but on the local disk of node rcas6080 (corresponds to /home/starreco/reco directory in the local disk of rcas6080.rcf.bnl.gov). We can even avoid the repetition of rcas and have just starrcfrcas:/6080/home/starreco/reco/
• starrcfrcas:/rcas6081/home/starreco/reco/ - another replica location for STAR reconstructed data on the local disk (corresponds to /home/starreco/reco directory in the local disk of rcas6081.rcf.bnl.gov)

Gabriele Carcassi - page was last modified