Implementing SMB Semantics in a Linux Cluster

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" summary

Samba implements SMB share modes and leases in user space using a local TDB and a cluster layer CTDB clustered TDB that keeps a central open-file table with one entry per open handle, including delete-prevention and delegation state. Large records (tens of thousands of openers) force heavy cluster shuffling so a summary record bitmask plus lazy updates avoids full-array scans. Benchmarking shows roughly 100x speedup on a file with ~5,000 openers. Next steps: move record locks into a user-space locking library and expose per-node summaries for local-fast common cases.

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" chapters (10)

1. 0:00Intro
2. 1:58What is Samba?
3. 3:10What is SMB?
4. 5:26Samba architecture
5. 7:22SMB share modes and leases
6. 11:20Implementation of SMB locking
7. 15:15ctdb Architecture
8. 20:19Scalability work on progress
9. 24:56Next steps
10. 27:14Questions?

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