URI | http://purl.tuc.gr/dl/dias/4D14007E-1B71-4E9B-98A8-35CD5BB7D49F | - |
Αναγνωριστικό | http://www.softnet.tuc.gr/~minos/Papers/sigmod96-cam.pdf | - |
Γλώσσα | en | - |
Μέγεθος | 12 pages | en |
Τίτλος | Multi-dimensional resource scheduling for parallel queries | en |
Δημιουργός | Garofalakis Minos | en |
Δημιουργός | Γαροφαλακης Μινως | el |
Δημιουργός | Ioannidis, Yannis, 1930- | en |
Εκδότης | Association for Computing Machinery | en |
Περίληψη | Scheduling query execution plans is an important component of
query optimization in parallel database systems. The problem is
particularly complex in a shared-nothing execution environment,
where each system node represents a collection of time-shareable
resources(e.g., CPU(s), disk(s), etc.) and communicates with other
nodes only by message-passing. Significant research effort has
concentrated on only a subset of the various forms of intra-query
parallelism so that scheduling and synchronization is simplified.
In addition, most previous work has focused its attention on
one-dimensional models of parallel query scheduling, effectively
ignoring the potential benefits of resource sharing. In this paper,
we develop an approach that is more general in both directions,
capturing all forms of intra-query parallelism and exploiting
sharing of multi-dimensional resource nodes among concurrent plan
operators. This allows scheduling a set of independent query tasks
(i.e., operator pipelines) to be seen as an instance of the multidimensional
bin-design problem. Using a novel quantification of
coarse grain parallelism, we present a list scheduling heuristic
algorithm that is provably near-optimal in the class of coarse
grain parallel executions (with a worst-case performance ratio that
depends on the number of resources per node and the granularity
parameter). We then extend this algorithm to handle the operator
precedence constraints in a bushy query plan by splitting the
execution of the plan into synchronized phases. Preliminary
performance results confirm the effectiveness of our scheduling
algorithm compared both to previous approaches and the optimal
solution. Finally, we present a technique that allows us to relax the
coarse granularity restriction and obtain a list scheduling method
that is provably near-optimal in the space of all possible parallel
schedules. | en |
Τύπος | Δημοσίευση σε Συνέδριο | el |
Τύπος | Conference Publication | en |
Άδεια Χρήσης | http://creativecommons.org/licenses/by/4.0/ | en |
Ημερομηνία | 2015-12-01 | - |
Ημερομηνία Δημοσίευσης | 1996 | - |
Θεματική Κατηγορία | Databases | en |
Βιβλιογραφική Αναφορά | M. Garofalakis and Y. Ioannidis, "Multi-dimensional resource scheduling for parallel queries", in ACM SIGMOD International Conference on Management of Data, June 1996, pp. 365-376. | en |