27.7. Garbage Collector

27.7. Garbage Collector
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Garbage Collector related configuration can be separated to two distinct groups:

Garbage Collector Settings

Allows to slightly change semantics of the Garbage Collector:

[ Settings/ObjectManagement/GC ]
can_run_any_time : boolean = false

Set this to true to allow GC to run even when objects are or might be active. Since active objects can not be deleted and are not treated as GC roots this may cause that migration groups will not be deleted atomically. See System::dispose_gc_root().

Garbage Collector Tuning

Controls automatic triggering of the Garbage Collector runs. Expert knowledge is required in order to be able to change these settings without causing a serious harm to the application performance.

[ Settings/ObjectManagement/GC ]
max_iterations_per_tick : integer = 256 
max_run_period : float = 30 
limit_delta : integer = 50 
max_limit_delta_fraction : float = 2 
thrashing_ratio : float = 0.8 
thrashing_coef : float = 0.2 
lazy_ratio : float = 0.5 
lazy_coef : float = 1.2 
max_unpin_time_delta : float = 1

	Maximum number of internal GC iterations within a GC tick.
	Maximum time difference between two GC runs.
	Trigger next GC run when object count reaches the current limit delta value plus number of local objects at the time of the previous GC run. Adapted at the end of the GC run.
	Maximum limit delta propotionally to the total number of local objects.
	The GC gets in the "thrashing mode" if number of finalized objects at the last GC run is greater than thrashing_ratio multiplied by the total number of local objects.
	Limit delta adaptation coefficient used when the GC is in "thrashing mode".
	The GC gets in the "lazy mode" if number of finalized objects at the last GC run is less than lazy_ratio multiplied by the total number of local objects.
	Limit delta adaptation for the "lazy mode".
	Issue a warning if objects have been active-pinned longer than the preset value (to get information on what active pinning is, consult the Massiv Core Reference Guide). Used for application performance and migration stalls tuning due to object pinning.

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