Hive converts multi-step map reduce job into stages. Some of these stages are dependent on each other some are not. If you set hive.exec.parallel=true and hive determines that some stages of the job do not depend on each other it may run more then one at once (currently it only runs one at a time).
So the result is hive can use more cluster resources to satisfy complex queries in some cases. Edward On Mon, Sep 10, 2012 at 11:26 AM, Matouk Iftissen <[email protected]>wrote: > Hello every one, > > Can anyone tell me what impact can affect jobs (or queries) if we turn on > (make to true ) the propriety hive.exec.parallel (by default it is set > to false)? > > Thanks for your answers. > > > > Matouk Iftissen > > [email protected] > > [image: Description : > file:///D:/Documents%20and%20Settings/rco/Bureau/logo%20cyres/signature/Logo%20CYRES%20GROUPE.jpg] > > 19-21, rue Edouard Vaillant > > 37000 TOURS > > *Tèl. 02 47 68 48 50 * > > Fax 02 47 68 48 59 > > www.cyres.fr > > >
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