C H A P T E R
22
Parallel and Distributed Query
Proessing
Solutions for the Pratie Exerises of Chapter 22
Pratie Exerises
22.1
Answer:
a. When there are many small queries, interquer y parallelism gives good
throughput. Parallelizing eah of these small quer ies would inrease the
initiation overhead, without any signiant redution in response time.
b. With a few large queries, intraquer y parallelism is essential to get fast
response times. Given that there are large numbers of proessors and
disks, only intraoperation parallelism an take advantage of the parallel
hardware, for quer ies t ypially have few operations, but eah one needs
to proess a large number of tuples.
22.2
Answer:
FILL
22.3
Answer:
a. The speedup obt ained by parallelizing the operations would be oset by
the data transfer overhead, as eah tuple produed by an operator would
have to be transfer red to its onsumer, whih is running on a dierent
proessor.
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