Mark Sweep

The true challenge of this project was to take the existing reference counting system and move it over to the mark and sweep model in the existing code base without breaking old content.

这个项目真正的挑战在于替换：必须在已有代码基础上，把引用计数系统整个换成标记-扫描系统，而完全不破坏过去的内容。

The process has three major phases: mark, sweep, and compact

这个过程有三个主要阶段：mark、sweep和compact

Mark-sweep collectors also tend to leave the heap fragmented, which can cause locality issues and can also cause allocation failures even when sufficient free memory appears to be available.

标记-清除收集器还容易使堆产生碎片，这会产生区域性问题并可以造成分配失败，即使看来有足够的自由内存可用。

As you increase the heap size on a consistent workload, the mark and sweep phases will continue to take approximately the same length of time.

当您增加统一工作负载上的堆大小时，标记和清扫阶段将继续花费大致相同的时间完成操作。

Since WinRT is built on top of COM you have the same problems with the dichotomy between reference counting and mark-and-sweep garbage collectors.

由于WinRT是基于COM构建的，所以你同样会有引用计数和mark-and-sweep垃圾回收器之间无法融合的问题。

Optavgpause: Performs the mark and sweep concurrently while the application is running to minimize pause times; this provides the best application response times.

optavgpause：在应用程序运行时并发执行标记和清扫操作，以便最大限度缩短暂停时间；这将提供最理想的应用程序响应时间。

The time spent in GC pauses for the mark and sweep phases of a garbage collection are based on the number of live objects on the heap.

用于垃圾收集的标记和清扫阶段的GC暂停时间基于堆上的活动对象的数量。

Mark and sweep: Each piece of data is marked with a tag.

标记并清理（Mark and sweep）：每一块数据都被加上一个标签。

The same mark-sweep-compact collector is used, but much of the mark and sweep phases can be done as the application runs.

这种策略也使用“标记-清扫-压缩（mark-sweep-compact）”收集器，但大部分标记和清扫工作可以在应用程序运行时执行。

In this type of GC, only the mark and sweep phases of GC are run.

在这类GC内，只运行GC的mark和sweep阶段。

This is a Deferred Reference Counting ( DRC) mechanism combined with an incremental, conservative mark/ sweep collector.

它采用了一种延迟引用计数（Deferred Reference Counting，DRC）机制，并结合一个增量的、保守的标记/清除收集器。

Simple ( non-lazy) Mark Sweep GC executes mark and sweep atomically.

简单（非延迟）标记清理GC以原子方式执行标记和清理。

Optthruput: ( default in V7) Performs the mark and sweep operations during garbage collection when the application is paused to maximize application throughput.

optthruput：（默认）当应用程序暂停时，在垃圾收集过程中执行标记和清扫操作，以便最大限度提高应用程序吞吐量。

Lua has a mark-and-sweep garbage collector.

Lua具有一个标记-清理垃圾收集器。

A GC pause usually consists of two distinct phases: the mark and sweep phases.

GC暂停通常包括两个独立阶段：标记阶段和清理阶段。