1.26Object GC

Support for script-based garbage collection strategies.

Object GC

Properties
items	Single GC sensible items currently allocated.
th_active	Threshold of occupied memory above which the GC will enter the active mode.
th_normal	Threshold of occupied memory above which the GC will enter the normal mode.
usedMem	Memory used by the Falcon engine.
Methods
adjust	Sets or gets the automatic threshold levels adjust algorithm.
enable	Turns automatic GC feature on or off.
perform	Requests immediate check of garbage.

Properties

items

Single GC sensible items currently allocated.

th_active

Threshold of occupied memory above which the GC will enter the active mode.

th_normal

Threshold of occupied memory above which the GC will enter the normal mode.

Methods

adjust

Sets or gets the automatic threshold levels adjust algorithm.

GC.adjust( [mode] )

mode	The adjust mode used by the GC.
Return	The mode currently set.

Mode can be one of:

GC.ADJ_NONE: No adjust. All adjusting must be done manually.
GC.ADJ_STRICT: Aggressive adjustment strategy, forcing active collection whenever the memory grows.
GC.ADJ_LOOSE: Permissive adjustment strategy, forcing active collection only when memory grows promptly.
GC.ADJ_SMOOTH_FAST: Adjustment following the memory allocation status with some delay and a smooth asymptotic curve (fast adaption).
GC.ADJ_SMOOTH_SLOW: Adjustment following the memory allocation status with some delay and a smooth asymptotic curve (slow adaption).

enable

Turns automatic GC feature on or off.

GC.enable( mode )

mode	true to turn automatic GC on, false to turn it off.

Virtual machines and some heavy garbage generating functions call periodically a function that checks for the level of allocated memory to have reached a critical point. When there is too much allocated memory of uncertain status, a garbage collecting loop is started.

By setting this property to false, this automatic control is skipped, and allocated memory can grow up to physical process limits (or VM memory limit constraints, if provided). Setting this value to true will cause VM to perform memory control checks again with the usual strategy.

In case the script is sure to have generated a wide amount of garbage, it is advisable to call explicitly GC.perform() before turning automatic GC on, as the "natural" collection loop may start at any later moment, also after several VM loops.

perform

Requests immediate check of garbage.

GC.perform( [wcoll] )

wcoll	Set to true to wait for the collection of free memory to be complete.
Return	true if the gc has been actually performed, false otherwise.

Suspends the activity of the calling Virtual Machine, waiting for the garbage collector to complete a scan loop before proceeding.