Arguments: &key old old-symbols new global-gc tenure expand sift-old-areas pack-heap verbose
This function attempts to restructure the Lisp heap according to the programmer's wishes. These wishes may call for old or new space to be increased in size (usually doable unless the operating system refuses to give up the needed extra space) or to be reduced in size (sometimes doable, but gaps -- foreign data -- above newspace or between the top oldspace and newspace may prevent resizing). Note that other gsgc parameters or requirements may also prevent resizing. This function can modify newspace, the top oldspace, and can coalesce two or more adjacent oldspace areas into one. Arguments control whether a global gc and/or tenuring of objects in newspace are forced prior to resizing.
| Argument | Values and effects |
| verbose | If non-nil (default nil), print information about what function is doing. |
| old | For each argument, the number of bytes which should be free in that area (oldspace, oldspace symbols, newspace) after this function returns. Other gsgc parameters may affect the number of free bytes, so the values specified are lower limits. No 5.0/5.0.1 platforms stores symbols separately in oldspace so the value of old-symbols has no effect in release 5.0/5.0.1. old and old-symbols default to 0. new defaults to
|
| old-symbols | |
| new | |
| global-gc | If true, do a global gc before other
actions. Defaults to nil but note that a (perhaps
second) global gc is also done later if
sift-old-areas and
pack-heap are both t. |
| tenure | If true then tenure all possible data
in newspace after processing the global-gc
keyword argument but before any other keyword values. Defaults to
nil. |
| expand | If true then expand oldspace or symbol
oldspace if necessary, otherwise do nothing if the requested
amount is not free. Defaults to t. |
| sift-old-areas | Move data in oldspace down to the oldest oldspace area
possible. The hope is that the lower (older) oldspace areas will
fill up, leaving the higher (newer) areas empty (or emptier). If
both this argument and pack-heap are true, a
global gc will occur after sifting and then adjacent empty
oldspace areas will be coalesced if possible. Defaults to
t. The global gc that occurs if this argument and
pack-heap are both true can take an
appreciable time so make this argument nil when time
is an issue. (Note: in releases prior to 6.0, the argument pack-areas
could be used to provide similar functionality to sift-old-areas.
In 6.0, the argument pack-areas has been removed and
is no longer valid.) |
| pack-heap | Reduce the size of the top (newest) old area as much
as possible. Defaults to t. |
See gc.htm for more information on garbage collection and gsgc parameters.
The documentation is described in introduction.htm and the index is in index.htm.
Copyright (c) 1998-2000, Franz Inc. Berkeley, CA., USA. All rights reserved.
Created 2000.10.5.