The planning team began by calculating the number of objects that will be stored on DASD, tape, and optical storage.
Calculate the value of ns as:
ns = (10 000 + (10 000 x 30)) x 1.1 = 341 000
Calculate the value of nl as:
nl = (10 000 + (10 000 x 7)) x 1.1 = 88 000
Calculate the number of small objects on optical and tape storage as:
os = ((10 000 x 30) x 1.1) - ns = 330 000 - 341 000 = 0
Calculate the number of large objects on tape and optical storage as:
ol = ((10 000 x 1307) x 1.1) - nl = 14 377 000 - 88 000 = 14 289 000
Calculate the total number of objects retained on tape and optical storage as:
ot = os + ol = 0 + 14 289 000 = 14 289 000
Calculate the value of nt as:
nt = ns + nl + ot
nt = 341 000 + 88 000 + 14 289 000 = 14 718 000
Calculate the storage needed for the object storage database data sets (see Table 1).
Table, index, or data set | Calculations |
---|---|
Object directory data set GROUP00.OSMDTS | tracks = nt ÷ (23 x b) |
Object directory index 1 |
tracks = nt ÷ (260 x b) |
Object directory index 2 |
tracks = nt ÷ (166 x b) |
Object directory index 3 |
tracks = nt ÷ (68 x b) |
Small object table index |
tracks = ns ÷ (68 x b) |
Small object table |
tracks = (ns ÷ b) x 1.1 |
Small object table |
tracks = (ns ÷ b) ÷ "floor" (4074 ÷ (aos + 61)) x 1.1 |
Large object table index |
tracks = nl ÷ (65 x b) |
Large object table |
cylinders = nl ÷ (32 746 ÷ ( aos + 63) x 22) x 1.1 |
Large object table |
(32 746 ÷ (aos + 63)) results in: |
LOB base table GROUP00.OSMLBTS | tracks = nlob ÷ (52 x b) x 1.1 |
LOB base index GROUP00.OTLOBX1 | tracks = nlob ÷ (68 x b) |
LOB auxiliary table GROUP00.OSMLATS | cylinders = nlob ÷ ((32 746 ÷ aos) x cb) x 1.1 |
LOB auxiliary index GROUP00.OTLOBAX1 | tracks = nlob ÷ (195 x b) |
Table 2 summarizes the storage space calculations.
|
Tracks needed | Cylinders needed |
---|---|---|
GROUP00.OSMDTS | 53 326 | 3 555 |
GROUP00.OBJDIRX1 | 4 717 | 315 |
GROUP00.OBJDIRX2 | 7 389 | 493 |
GROUP00.OBJDIRX3 | 18 037 | 1 203 |
GROUP00.OBJT04X1 | 418 | 28 |
GROUP00.OSMOTS04 |
31 259 | 2 084 |
GROUP00.OSMOTS04 |
15 630 | 1 042 |
GROUP00.OBJT32X1 | 112 | 8 |
GROUP00.OSMOTS32 | — | 8 611 |
GROUP00.OSMOTS32 |
— | 2 200 |
GROUP00.OSMLBTS |
88 | 6 |
GROUP00.OTLOBX1 |
62 | 5 |
GROUP00.OSMLATS |
— | 4 886 |
GROUP00.OTLOBAX1 |
22 | 2 |
It is important to remember that the object directory table has an entry for every object within that Object storage group. This directory includes objects in the 4 KB object table, in the 32 KB object table and in the LOB storage structure, plus objects in the file system sublevel and on tape and optical storage. The 4 KB object table, the 32 KB object table, and the LOB storage structure have only the objects that are stored on in the DB2 sublevel. When an object is stored directly in the file system or on tape or optical storage, an entry is created in the object directory, but the object itself is not stored in either the 4 KB or the 32 KB object tables or the LOB storage structure. For all objects stored directly on tape or optical storage, the calculations for small and large objects on tape or optical storage (see item 3) will provide the values needed for the object directory space.
If the object being stored is less than or equal to 256M and greater than or equal to 32KB, then LOB=P requires OAM to query DB2 to see if the LOB base table view exists for a given object storage group. If the LOB base table view does exist for a given object storage group, large objects are stored in the associated LOB storage structure. If the LOB base table view does not exist, large objects are stored in the 32KB data table.