Snapbench? Run your favorite benchmark with long-open snapshots and observe how your MVCC engine of choice responds.
smalldatum.blogspot.com/2015/07/the-im
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Need to redo this and include Postgres
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The fact that RocksDB on MySQL is smarter than InnoDB about "intermediate unneeded versions" seems significant to me. I suspect that addressing this in InnoDB is much harder, for very fundamental reasons. Reasons that your MVCC taxonomy (which is great btw) didn't quite capture.
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Not sure we have a good & short name for this, but we do have a long open feature request for InnoDB:
bugs.mysql.com/bug.php?id=749
Maybe we got lucky WRT RocksDB. It is easier there to have it prune intermediate versions that are no longer visible.
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I believe RocksDB has what "Options in Physical Database Design" paper (from Graefe) calls "structural updates", and "physical pointers" -- like Postgres, but unlike InnoDB and Oracle (especially unlike the latter IIUC). This has many important consequences, good and bad, IME.
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