Expert Oracle Exadata - Parent Directory

CHAPTER 14 STORAGE LAYOUTASM Disk GroupsDATA_DGRECO_DGSYSTEM_DGCELL01CELL03CELL01CELL03CELL01CELL03CELL02CELL02CELL02Linux O/SGrid DisksStorage Cell 1Failure Group: CELL01Storage Cell 2Failure Group: CELL02SYSTEM_DGDATA_DGRECO_DGCell Disk 1 Cell Disk 2 Cell Disk 3 Cell Disk 4 Cell Disk 10 Cell Disk 11 Cell Disk 12SYSTEM_DGDATA_DGRECO_DGCell Disk 1 Cell Disk 2 Cell Disk 3 Cell Disk 4Cell Disk 10 Cell Disk 11 Cell Disk 12Storage Cell 3Failure Group: CELL03SYSTEM_DGDATA_DGRECO_DGCell Disk 1 Cell Disk 2 Cell Disk 3 Cell Disk 4Cell Disk 10Cell Disk 11 Cell Disk 12Figure 14-4. Storage virtualization on ExadataStorage AllocationDisk drives store data in concentric bands called tracks. Because the outer tracks of a disk have moresurface area, they are able to store more data than the inner tracks. As a result, data transfer rates arehigher for the outer tracks and decline slightly as you move toward the innermost track. Figure 14-5shows how tracks are laid out across the disk surface from fastest to slowest.473