EOS

CERN’s open-source disk storage system and the floor under almost everything else. Built on the XRootD framework for remote access, with a namespace held as an in-memory cache backed by QuarkDB — a redesign that removed the old ceiling, where the metadata service could hold no more than fitted in one machine’s RAM. Reachable through FUSE, HTTPS/WebDAV, XRootD, gRPC, S3 and SMB, and running on commodity hardware with disks in JBOD.

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Topology

• Part of: storage-and-data
• Uses: xrootd — its remote access protocol.
• Cites: afs-phaseout-paper — it absorbed AFS’s live-data role.
• Cites: eos-docs — architecture and access methods.
• Cites: eos-run3-storage — the capacity behind Run 3.