Single Query Optimization for Tertiary Memory
نویسندگان
چکیده
We present query execution strategies that are optimized for the characteristics of tertiary memory devices. Traditional query execution methods are oriented to magnetic disk or main memory and perform poorly on tertiary memory. Our methods use ordering and batching techniques on the I/O requests to reduce the media switch cost and seek cost on these devices. Some of our methods are provably optimal and others are shown to be superior by simulation and cost formula analysis.
منابع مشابه
Database Systems for Efficient Access to Tertiary Memory
Tertiary storage devices have long been in use for storing massive amounts of data in le-oriented mass storage systems. However, their use in database systems is relatively new. Database systems associate more structure to the data than just raw sequence of bytes. Hence if they are allowed control of the tertiary memory devices, they can greatly reduce access cost by doing more informed caching...
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