如这样的日志: CMS: abort preclean due to time 634260.811: [CMS-concurrent-abortable-preclean: 4.549/5.020 secs] [Times: user=4.91 sys=0.05, real=5.02 secs]
Phase Type Reason ------------------------------------ CMS initial mark stop-the-world phase phase to mark the objects CMS marking concurrent phase actual marking objects CMS precleaning concurrent phase precleaning CMS abortable preclean concurrent phase pre-cleaning to avoid long STP ahead CMS Remark stop-the-world phase Remarking (moving objects from one segment to another) CMS sweep concurrent phase Sweeping phase CMS reset concurrent phase Reset the marking tables ------------------------------------ CMS回收有这些阶段,其中init mark和remark会stop world
abortable preclean 阶段是为了减少remark的工作,到达指定的时间,它就结束了 这个时间是CMSMaxAbortablePrecleanTime指定的,默认是5秒。
由于它叫CMS-concurrent-abortable-preclean, 带concurrent的都是并行的,所以不影响程序运行。
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