Compute shader memory usage jumps to about 100 gigabyte after about a minute

Questions & Answers
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1

I am learning compute shaders right now and have a very simple compute shader that I made.

However, after about a minute, my memory usage will have jumped to about 100 gigabytes.
Any idea why?

TestShader.compute

// Each #kernel tells which function to compile; you can have many kernels
#pragma kernel CSMain

// Create a RenderTexture with enableRandomWrite flag and set it
// with cs.SetTexture
RWTexture2D<float4> Result;

float2 res;
float thingRadius;

float colour;

float x;
float y;


struct Circle{
    float2 position;
    float scale;
};

float rand (float2 co)
{
    return(frac(sin(dot (co.xy, float2(12.9898, 78.233))) * 43758.5453)) * 1;
}

[numthreads(8,8,1)]
void CSMain (uint3 id : SV_DispatchThreadID)
{
    
    x = id.x / res.x;
    y = id.y / res.y;

    colour = abs(x - 0.5) * thingRadius + abs(y - 0.5) * thingRadius;


    Result[id.xy] = float4(colour, colour, colour, 0.0);
}
code here

ComputeShaderTest.cs

using UnityEngine;

public class ComputeShaderTest : MonoBehaviour
{
    public ComputeShader computeShader;

    public RenderTexture renderTexture;

    public int resolutionX;
    public int resolutionY;

    public float thingRadius = 1f;

    private void Start()
    {
        renderTexture = new RenderTexture(resolutionX,resolutionY,24);
        renderTexture.enableRandomWrite = true;
        renderTexture.Create();

        computeShader.SetTexture(0, "Result", renderTexture);
        computeShader.Dispatch(0,renderTexture.width / 8, renderTexture.height / 8, 1);
    }

    private void OnRenderImage(RenderTexture source, RenderTexture destination)
    {
        if(renderTexture != null)
        {
            renderTexture = new RenderTexture(resolutionX, resolutionY, 24);
            renderTexture.enableRandomWrite = true;
            renderTexture.Create();
        }

        computeShader.SetTexture(0, "Result", renderTexture);
        computeShader.SetVector("res", new Vector4(renderTexture.width,renderTexture.height));
        computeShader.SetFloat("thingRadius", thingRadius);

        computeShader.Dispatch(0, renderTexture.width / 8, renderTexture.height / 8, 1);

        Graphics.Blit(renderTexture, destination);
    }
}
2

I found the solution.

I was creating a new RenderTexture every time OnRenderImage was being called.
Only calling it in the Start method fixed the problem!