Transcript Cohera
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Dewitt Was Right
By Michael Stonebraker
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DWR
Grids (cells, blades)
Cheapest computing on the planet (coming)
Shared nothing
How does this relate to data bases?
Go read about Gamma (circa 1985) M.I.T.
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But…….
Buy the dreaded 2 phase commit
Bad sandbox to play in M.I.T.
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Suppose
Insist on replication of every table
Done by SLAC, Walmart and most warehouses
Disk space is cheap
Replicas need not be organized the same way
Process every update twice (independently)
In general provide K-safety M.I.T.
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Crash Recovery
Rebuild damaged object from a replica, not from a redo log
Get rid of
Redo (but not undo)
Truncate undo log at EOT
2 phase commit (prepare message) M.I.T.
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Net Result - No Mohan
New sandbox:
How to efficiently rebuild objects (especially partially damaged ones) from replicas M.I.T.