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Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. layout: publication title: Publication subtitle: > RHEEMix in the Data Jungle: A Cost-based Optimizer for Cross-Platform Systems link-name: VLDB Journal 29(6), 2020 img-thumb: assets/img/screenshot/rheem.png authors: Sebastian Kruse, Zoi Kaoudi, Sanjay Chawla, Felix Naumann, Bertty Contreras-Rojas and Jorge-Arnulfo Quiané-Ruiz year: 2020 month: 11 day: 01 link-paper: assets/pdf/paper/journal_vldb.pdf link-external: false

Data analytics are moving beyond the limits of a single platform. In this paper, we present the cost-based optimizer of Rheem, an open-source cross-platform system that copes with these new requirements. The optimizer allocates the subtasks of data analytic tasks to the most suitable platforms. Our main contributions are: (i) a mechanism based on graph transformations to explore alternative execution strategies; (ii) a novel graph-based approach to determine efficient data movement plans among subtasks and platforms; and (iii) an efficient plan enumeration algorithm, based on a novel enumeration algebra. We extensively evaluate our optimizer under diverse real tasks. We show that our optimizer can perform tasks more than one order of magnitude faster when using multiple platforms than when using a single platform