Performance Tuning for Content Manager

Chapter 4. Planning for performance 95

laboratory conditions and a well-optimized system; these conditions might not be

the same for your application so make allowance for that.

The report also provides relative performance measures for the

Resource

Manager

capacity. The Resource Manager is an application that runs and uses

processor and memory capacity as well as I/O capacity.

4.5 Estimating storage requirements

Apart from processing capacity, the system must also allow sufficient data

storage capacity. Part of the planning must be to calculate the projected storage

requirements now and into the future. Storage is required for the Library Server

as well as the Resource Managers. The Library Server holds the data in the

Library Server database and its size must be estimated and accounted for. The

Resource Manager, as the primary data storage component, must have sufficient

space to hold the images, documents, and files that make up the system, in

combination with the TSM system, if used. It also has a database and we need to

include this in our storage calculations.

Library Server database

The size of the Library Server database grows as the number of documents and

folders grows. To estimate its size, you need to know the number of documents or

folders you expect to have in the system, the number that will be in workflow at a

given time, the number of folders you expect each item to be contained in, the

number of resource objects you expect to have, the total length of the attributes

of each item type, and the number of items that will be in each of the item types.

To estimate the size of the database accurately, we have to understand all of the

database tables and how they are used. The database tables are documented in

the API online reference, so we can calculate the table sizes exactly. This is quite

tedious. Alternatively, we can measure sample systems and extrapolate,

approximate by sizing only the largest tables, usually the item type tables, and

then allowing additional space for the remaining control tables.

Each folder or item will have:

 A row in the item type table and, where applicable, items in the child

component tables

 A row in the links table for every link, or it “contains” the relationship it has

 A row in the document routing tables for every process in which it participates

Each document will have:

 A row in the item type table and, where applicable, items in the child

component tables

96 Performance Tuning for Content Manager

 A row in the parts table for that item type

 A row in the media object class table for that part type

 A row in the document routing tables for every process in which it participates

Resource items will have:

 A row in the item type table and, where applicable, items in the child

component tables

 A row in the media object class table for that part type

 A row in the document routing tables for every process in which it participates

In each of these rows, there is a certain amount of system data. See Table 4-1 for

root component system data, and Table 4-2 on page 97 for child component

system data. There is also user-defined attribute data. It is possible to calculate

the row lengths for each of the major tables; multiply them by the projected

numbers of items; add in factors for the database row, page, and table overheads,

and the other system tables; then add in extra space for the user and system

indexes. For more about calculating database table and index sizes, see IBM DB2

Universal Database Version 8.2 Administration Guide: Planning, SC09-4822.

Table 4-1 System entries for root component tables

Column name Type Length Scale Nulls

COMPCLUSTERID INTEGER 4 0 No

COMPONENTID CHARACTER 18 0 No

ITEMID CHARACTER 26 0 No

VERSIONID SMALLINT 2 0 No

ACLCODE INTEGER 4 0 No

SEMANTICTYPE INTEGER 4 0 No

EXPIRATIONDATE DATE 4 0 Yes

COMPKEY VARCHAR 23 0 No

CREATETS TIMESTAMP 10 0 No

CREATEUSERID CHARACTER 32 0 No

LASTCHANGEDTS TIMESTAMP 10 0 No

LASTCHANGEDUSERID CHARACTER 32 0 No