Kernel-Managed Swap Facility (KMSF) Manual

Managing KMS Files
Kernel-Managed Swap Facility (KMSF) Manual—425824-005
3-2
Key Indicators for KMSF Usage
display the NSK subsystem name. By monitoring the EMS logs or ViewPoint for these
messages, you can avoid actively checking your swap files.
Key Indicators for KMSF Usage
Monitor the following key indicators to determine whether your KMSF configuration is
successfully meeting the needs of the system.
•
Process creation error 55 (the specified space guarantee cannot be allocated)
indicates that there is not enough swap space for a processor to start new
processes. The existing swap file or files might be full or disabled for use by new
processes. Alternately, swap files might have been deleted or have a STOP
command or DELETE command pending.
Before any new processes can be started, you must use NSKCOM to increase the
available swap space for the processor. If process creation errors prevent you from
running NSKCOM in the processor, run NSKCOM in another processor to
configure the additional swap space.
•
Peak usage. Peak usage represents the total number of memory pages that have
ever been reserved for the swap file. How high you allow the peak usage to go
depends on your site and the type of programs you run.
If you run critical programs or programs that use large amounts of memory, try to
keep peak usage under 85 percent of total capacity. If you run noncritical or
smaller programs, you might allow peak usages of as much as 90 percent of total
capacity. Use the STATUS SWAPFILE command (see page 4-23) to view the peak
usage for a swap file.
•
Reservation creation failures. Reservation creation failures represent the number
of times that a program’s needs for memory exceeded the memory available and
prevented the program from running. Use the STATUS KMSF command (see page
4-23) to view reservation creation failures.
•
Operator messages indicating that KMSF swap space is needed.
Using NSKCOM to Monitor KMS Space
Run NSKCOM by typing “NSKCOM” at the HP Tandem Advanced Command
Language (TACL) prompt. When NSKCOM starts, it automatically displays your
current configured swap files, as shown in Figure 3-1 on page 3-3. The NSKCOM
opening banner does not display default swap files. Following the banner, the
NSKCOM prompt NSK- appears.