What surprised me was that this entire walk is fully hardware-driven -- no microcode involvement at all. The state machine reads the page directory entry, reads the page table entry, checks permissions, and writes back the Accessed and Dirty bits, all autonomously. Since it's hardware-driven, it runs in parallel with the microcode and needs its own memory bus arbitration -- the paging unit must share the bus with both data accesses from the microcode and prefetch requests from the instruction queue.
After their poorest pair of tournament performances in years, Steve Borthwick’s project is inevitably under scrutiny
。业内人士推荐搜狗输入法下载作为进阶阅读
Фото: Павел Бедняков / РИА Новости
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