XCF maintains an entry in the note pad catalog structure for each note pad defined in the sysplex. The size of the note pad catalog structure is proportional to the number of note pads that can be defined in the sysplex. The following table shows sample catalog structure sizes for different note pad counts, assuming the coupling facility is at CFLEVEL 18.

The CF Structure Sizer (CFSizer) can also be used to simplify the task of calculating the size of the note pad catalog structure.

The IBM® CF Structure Sizer (CFSizer) can be accessed at http://www.ibm.com/systems/support/z/cfsizer/. To size the catalog structure, click on the OEM link and input the catalog structure attributes.

When determining the size of the note pad catalog structure, consider the following required structure attributes:

• A list structure type that has 10 list headers and uses both entry and adjunct data
• A lock table entry count of 0
• Can be altered
• The maximum number of list entries depends on the maximum number of note pads that will be in use in the sysplex at any given time. Use the following formula to calculate the number of maximum list entries:

  #max_list_entries = 32 + #note_pads

  where #note_pads is the maximum number of note pads that will be in use in the sysplex at any given time.
• The maximum number of data elements is ten times the maximum number of entries. For example, if the maximum number of list entries is determined to be 532, then the maximum number of data elements is 5320.
• A maximum of 255 data elements per entry
• A list entry can be located by a key value
• An element increment number of 1 (the size of each element is 256 bytes)
• Both entry keys and secondary keys might be used when processing list entries
• An event monitoring controls (EMC) count of 0
• Resides in a coupling facility of CFLEVEL 9 or higher

After determining the estimated structure size, if you need to change the coupling facility structure size later, you can do so using either of the following two methods:

• Dynamically alter the coupling facility structure size by entering the SETXCF START,ALTER command or issuing the IXLALTER service. However, the actual structure size cannot exceed the maximum structure size value or fall below the minimum structure size value.
• Update the CFRM policy with the new coupling facility size, activate the policy, and then have the operator initiate a rebuild of the structure.