System M: a transaction processing testbed for memory resident data

System M is an experimental transaction processing testbed that runs on top of the Mach operating system. Its database is stored in primary memory. The structure and algorithms used in System M are described. The checkpointer is the component that periodically sweeps memory and propagates updates to a backup database copy on disk. Several different checkpointing (and logging) algorithms were implemented, and their performance was experimentally evaluated.<
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