Caché Installation Guide - InterSystems Documentation

Calculating System Parameters for OpenVMS
OpenVMS Working Set Parameters
Parameter
WSDEFAULT
WSQUOTA
WSEXTENT
WSINC
WSDEC
BORROWLIM
PFRATH (Page Fault Rate
High)
PFRATL (Page Fault Rate
Low)
Definition
Initial size of the working set in 512-byte pagelets.
Maximum guaranteed amount of physical memory, in
pagelets, that OpenVMS allocates to a given process.
WSQUOTA is limited by the value of the SYSGEN
parameter WSMAX. If WSQUOTA is larger than
WSMAX, the user only has access to the amount of
memory in WSMAX.
Indicates the maximum amount of physical memory
which the process can own. The amount WSEXTENT
less WSQUOTA is called “borrowed” memory, which
is only allocated to the process if the system's current
free list size exceeds the amount specified in the
parameter BORROWLIM.
The number of pagelets by which the working set size
of a process is increased when it needs to grow.
The number of pagelets by which the working set size
of a process is decreased when it needs to be reduced
in size.
Minimum number of pagelets that must be in the free
page list before a process can borrow pages in WSINC
amounts up to WSEXTENT pages.
Indicates the number of page faults that must occur
within the period specified by AWSTIME, before
OpenVMS makes an “automatic working set
adjustment” to increase the working set by WSINC.
If the number of page faults is less than this value,
OpenVMS makes an “automatic working set
adjustment” to decrease the working set by WSDEC,
but not below the point set by AWSMIN.
Note:
While parameters have units of pagelets, OpenVMS allocates memory in pages. For this
reason, the parameter values you choose should be even multiples of the number of pagelets
per page. OpenVMS automatically rounds these parameters if you do not follow this guideline.
70 Caché Installation Guide