GarbageCollector.GCMode

描述

设置和获取全局垃圾回收器工作模式。

设置全局工作模式会更改整个应用程序的垃圾回收器行为。

在 WebGL 平台上和编辑器中不受支持。

建议仅在应用程序级别更改垃圾回收器工作模式，不要在第三方库中更改它。

订阅 GarbageCollector.GCModeChanged 事件可在垃圾回收器模式更改时收到通知。

**禁用垃圾回收器** 通过分配 GarbageCollector.Mode.Disabled 可以完全禁用垃圾回收器。这意味着垃圾回收器线程将永远不会停止您的应用程序来执行收集。此外，调用 System.GC.Collect() 将无效并且不会启动收集。禁用垃圾回收器必须非常小心，因为禁用垃圾回收器后的持续分配将导致内存使用量的持续增加。

建议仅为长期的分配禁用垃圾回收器。例如，在游戏中，应该为一个关卡分配所有必需的内存，然后禁用垃圾回收器以避免关卡期间的开销。在关卡结束并释放所有内存之后，可以再次启用垃圾回收器，并可在加载下一关卡之前调用 System.GC.Collect() 来回收内存。

Controlling the Garbage Collector manually You can set GCMode to GarbageCollector.Mode.Manual. This disables automatic invocations of the garbage collector, but still allows you to manually perform garbage collection. Manual collection gives you control over when collections happen, so you can fine-tune the smoothness of your content or your memory usage. Call either System.GC.Collect() for a full, blocking collection, or GarbageCollector.CollectIncremental to perform incremental garbage collection.

See Also: GarbageCollector.Mode.Enabled, GarbageCollector.Mode.Disabled, GarbageCollector.Mode.Manual.

using System;
using UnityEngine;
using UnityEngine.Scripting;

public class GarbageCollectorExample
{
    static void ListenForGCModeChange()
    {
        // Listen on garbage collector mode changes.
        GarbageCollector.GCModeChanged += (GarbageCollector.Mode mode) =>
        {
            Debug.Log("GCModeChanged: " + mode);
        };
    }

    static void LogMode()
    {
        Debug.Log("GCMode: " + GarbageCollector.GCMode);
    }

    static void EnableGC()
    {
        GarbageCollector.GCMode = GarbageCollector.Mode.Enabled;
        // Trigger a collection to free memory.
        GC.Collect();
    }

    static void DisableGC()
    {
        GarbageCollector.GCMode = GarbageCollector.Mode.Disabled;
    }
}

Using the GCMode API.

using System;
using UnityEngine;
using UnityEngine.Profiling;
using UnityEngine.Scripting;

public class GCManualControl : MonoBehaviour
{
    // Perform an incremental collection every time we allocate more than 8 MB
    const long kCollectAfterAllocating = 8 * 1024 * 1024;

    // Perform an instant, full GC if we have more than 128 MB of managed heap.
    const long kHighWater = 128 * 1024 * 1024;

    long lastFrameMemory = 0;
    long nextCollectAt = 0;

    void Start()
    {
        // Set GC to manual collections only.
        GarbageCollector.GCMode = GarbageCollector.Mode.Manual;
    }

    void Update()
    {
        long mem = Profiler.GetMonoUsedSizeLong();
        if (mem < lastFrameMemory)
        {
            // GC happened.
            nextCollectAt = mem + kCollectAfterAllocating;
        }
        if (mem > kHighWater)
        {
            // Trigger immediate GC
            System.GC.Collect(0);
        }
        else if (mem >= nextCollectAt)
        {
            // Trigger incremental GC
            UnityEngine.Scripting.GarbageCollector.CollectIncremental();
            lastFrameMemory = mem + kCollectAfterAllocating;
        }
        lastFrameMemory = mem;
    }
}

Manual GC control using GarbageCollector.Mode.Manual.