Virtual memory is conceptually simple but potentially devastating to performance. Every memory access must go through segmentation (add segment base, check limit) and then paging (look up the page table). Naively, paging alone requires two additional memory reads per access -- one for the page directory entry, one for the page table entry.
"To have that signal, you need that infrastructure, and that's where the planning system comes into play," Elliott says.
，更多细节参见同城约会
陆逸轩：那当然是一个因素，另外一个更重要的原因是，我清楚地知道，当下的表现可能会对我之后的人生产生深远的影响。这种“后果感”带来的压力是巨大的。相比之下，一场普通音乐会即便出现问题，通常也是不会改变你的人生走向的。
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