Storage Administration - Oracle Exadata Recipes: A Problem-Solution Approach - page 271

foreach (@UNIQCELLS) {
print "$_ has $cell{$_} grid disks\n";
}
%seen = ();
@UNIQGDS= grep { ! $seen{$_} ++ } @GDS;
foreach (@UNIQGDS) {
print "$_ is built on $cell{$_} grid disks\n";
}
%seen = ();
@UNIQDTL= grep { ! $seen{$_} ++ } @DTL;
foreach (@UNIQDTL) {
print "Distinct size and offset for : $_";
}

[oracle@cm01dbm01 source]$ ./griddisks.pl
Total grid disks: 174
cm01cel01: has 58 grid disks
cm01cel02: has 58 grid disks
cm01cel03: has 58 grid disks
DATA is built on 36 grid disks
DBFS is built on 30 grid disks
RECO is built on 36 grid disks
SDATA is built on 36 grid disks
SRECO is built on 36 grid disks
Distinct size and offsets for : DATA: Size 284G: Offset 32M
Distinct size and offsets for : DBFS: Size 29.125G: Offset 528.734375G
Distinct size and offsets for : RECO: Size 67G: Offset 425.046875G
Distinct size and offsets for : SDATA: Size 141G: Offset 284.046875G
Distinct size and offsets for : SRECO: Size 36.6875G: Offset 492.046875G
[oracle@cm01dbm01 source]$

In this output, we can glean the following information:

• Each storage cell has the same number of grid disks.

• There are five distinct types of grid disks across the cell disks, each with a different prefix and

likely intended for different database storage purposes.

• The size of each of the grid disks is uniform across all cell disks and storage cells.

• The byte offset is in the same location per grid disk on each cell disk.

• The

DATA grid disks were created first; the 32 MB offset means that the extents for each DATA*
grid disk were formatted 32 MB from the outermost tracks of each cell disk and continued
for 284 GB.

• The

SDATA grid disks were created next at an offset of 284 GB, continuing for 141 GB.

RECO grid disks were created next, then our SRECO disks, and finally the DBFS_DG grid disks.
Now that you have a clear picture of where each grid disk's extents are physically located on your cell disks, you
can begin your interleaving implementation.

• The