Expert Oracle Exadata - Parent Directory

CHAPTER 7 RESOURCE MANAGEMENTthumbing through the pages you’ve already read, Table 7-4 shows a summary of how we’ve configuredOracle Resource Manager for the SCRATCH and SNIFF databases in this chapter.Table 7-4. Summary of DBRM / IORM Resource AllocationI/O Management Type Allocation AssignmentCategory IORMCategories• APPS_CATEGORY• BATCH_CATEGORY• OTHERInterdatabase IORMDatabases• SCRATCH• SNIFF• OTHERIntradatabase IORMConsumer Groups• APPS• REPORTS• MAINTENANCE• OTHER_GROUPS70% at level 130% at level 1100% at level 360% at level 180% at level 2100% at level 370% at level 150% at level 250% at level 350% at level 3Consumer Groups• APPS• REPORTS, MAINTENANCE• OTHER_GROUPSDatabases• SCRATCH• SNIFF• All othersUser Accounts• KOSBORNE• RJOHNSON• TPODER• All other user accountsThere is a fixed order of precedence between the three IORM methods we’ve discussed. As I/Orequests traverse the layers of the IORM stack, they are divided and allocated by the next method. At thetop of the IORM hierarchy, 100% of I/O resources are available because the storage cell is not saturatedby I/O requests. The next level of the hierarchy is Category IORM, which allocates I/O at a 70/30 splitbetween the categories APPS_CATEGORY and BATCH_CATEGORY (at level 1). Any unconsumed I/O betweenthese two groups is available to the OTHER category at level 2.Next in the IORM hierarchy is the Interdatabase Plan. At the database level, the 70% allocated to theAPPS_CATEGORY category is further divided, giving 60% to the SCRATCH database on level 1, and 80% to theSNIFF database at level 2. Any other database receives 20% of the unallocated I/O from level 2, as well asaccess to any I/O that was not consumed by the SCRATCH and SNIFF databases on levels 1 and 2.The third and final tier of the IORM hierarchy is Intradatabase IORM. Our Intradatabase planfurther divides I/O allocation into the four DBRM consumer groups we created in the databases. TheAPPS consumer group gets top priority at 70% on level 1. The REPORTS group is allocated 50% at level 2.MAINTENANCE and OTHER_GROUPS share a 50/50 split of I/O that was unallocated or unconsumed at levels 1and 2.216