clearing memory after arrays are used in unity

Question

I want to clear memory from "spent" arrays of vectors or integers. Arrays themselves and values inside are no longer necessary. I am simply doing:

System.Array.Clear(SomeArray,0,SomeArray.Length );
SomeArray=null;

Does this clear the memory and it becomes available for other uses? Or does GC still have to do it? (if so how to do it without leaving any to GC )

P.S. I figured that iterating through and nulling each value is pointless since you can't null vector or int.

Thanks

Possible duplicate of [Force garbage collection of arrays, C#](http://stackoverflow.com/questions/1104352/force-garbage-collection-of-arrays-c-sharp) — Serlite, Oct 25 '16 at 19:50
(Or alternatively http://stackoverflow.com/questions/584017/how-to-delete-an-array-in-c also answers some questions about garbage collection.) — Serlite, Oct 25 '16 at 19:50
the only line you could potentially need is `SomeArray=null;` if `SomeArray` was a class level variable. Let Unity handle clearing the memory when it has time to do it. — Scott Chamberlain, Oct 25 '16 at 19:55

Pavan Chandaka · Accepted Answer · 2016-10-25T20:00:56.630

4

This method only clears the values of the elements; it does not delete the elements themselves.

Look into below documentation: https://msdn.microsoft.com/en-us/library/system.array.clear(v=vs.110).aspx

By setting NULL is not an indication to GC to collect it. Probably you can call GC.Collect(). refer https://msdn.microsoft.com/en-us/library/system.gc.collect(v=vs.110).aspx for more information.

Also keep in mind "GC.Collect" call is a overhead.

edited Oct 25 '16 at 20:00

answered Oct 25 '16 at 19:46

Pavan Chandaka

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for the love of everything todo with unity, do not call GC.Collect in a normal application flow, unless you are absolutely certain you have to, in which case i would triple check it another 10 times if you really need it. It usually indicates either bad process flow and/or inexperience. – Riaan Walters Oct 25 '16 at 20:56
I agree. it is a overhead, – Pavan Chandaka Oct 25 '16 at 20:59

Matias Cicero · Answer 2 · 2016-10-25T19:57:29.457

Setting SomeArray to null only tells the GC that the array is no longer referenced by that variable and may be available¹ for collection.

Garbage collection can happen at any time.

Until then, the array that was referenced by SomeArray will still occupy the same amount of memory. The only difference being that it would now contain zeroed elements.

¹ The array may be still being referenced by other variables. GC will only collect it when it is no longer referenced anywhere in your program.

clearing memory after arrays are used in unity

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