This screen helps you determine the relative CPU performance
impact of row caching. Poor CPU performance can result if many
hash table collisions occur.
This screen displays the following fields:
o Cache ID- the row cache identifier
o #Rows- the total number of rows in the row cache
o Table Size- the total number of hash table entries for the row
cache
Each character position of the screen identifies a specific hash
table entry. The character, if any, identifies the length of that
entry's queue. The asterisk (*) denotes a queue length of 10 or
more.
The line of "X"s indicates the end of the display. All blank
lines following the row of "X"s can be ignored.
Ideally, every space of the screen should be non-zero. A display
containing many long queues and a lot of blanks indicates poor
CPU utilization.
You can use the Config menu option to filter the Row Cache
Queue Length screen. Select this option, by typing the letter
C, to display the configuration submenu. The configuration
submenu contains a single option: "Filter Utilization Display".
Selecting this option will display the prompt "Enter row cache
threshold (0+) [current=1]: ". Any queue length which is less
than the specified utilization threshold will not be displayed.
By default, the utilization threshold is 0, so that all entries
on the screen are displayed, even those of length 0.
The number of rows in the row cache affects the size of the
corresponding hash table. Hash table queue lengths can be
controlled by increasing or decreasing the number of row cache
entries.
When there is more than one page of the Row Cache Queue Length
screen, the header section contains the page number currently
displayed and the total number of pages in the display. Use the
left angle bracket (<) key to go to the previous page and the
right angle bracket (>) key to go to the next page of the screen.
The Row Cache Queue Length screen is not recorded in the binary
output file produced using the Output qualifier. Consequently,
this screen is not available when you replay a binary file using
the Input qualifier.