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diff --git a/unix/os/doc/zawset.hlp b/unix/os/doc/zawset.hlp new file mode 100644 index 00000000..7d85bc5e --- /dev/null +++ b/unix/os/doc/zawset.hlp @@ -0,0 +1,42 @@ +.help zawset May84 "System Interface" +.ih +NAME +zawset -- adjust working set size +.ih +SYNOPSIS +.nf +zawset (requested_size, newsize, oldsize, textsize) + +int requested_size # desired working set size, bytes +int newsize # working set allocated, bytes +int oldsize # old working set size, bytes +int textsize # size of text segment +.fi +.ih +DESCRIPTION +Adjust the amount of physical memory allocated to a process, i.e., the +working set size on a virtual memory machine. The amount of additional +data space that can be allocated and used by a process without thrashing +on a virtual memory machine is \fInewsize\fR bytes minus some fraction +of the text segment size (executable instructions) and minus the data space +already in use. + +The actual working set size returned in \fInewsize\fR need not be what was +requested. The old working set size \fIoldsize\fR may be used to reset the +working set size of the process to its original value when the space is no +longer needed. If \fIrequested_size\fR is negative or zero the current size is +returned in both output arguments and the working set size is not changed. +On a nonvirtual memory machine the "working set size" is a machine constant +fixed by the addressing range of the hardware, hence the requested size is +ignored. +.ih +RETURN VALUE +Valid \fInewsize\fR, \fIoldsize\fR and \fBtextsize\fR are always returned. +.ih +NOTES +It is up to the high level code to supply the necessary heuristics to avoid +thrashing on a virtual memory machine. +.ih +SEE ALSO +zmalloc, zmfree, zraloc +.endhelp |