Okay, let's look at a sample problem.
好了,让我们来举个例子
Suppose we're given a computer with a 16-bit virtual address and a page size of 256 bytes.
假设一台电脑拥有16位虚拟位址 分页256字节
The system uses one-level page tables that start at address hex 400.
系统使用16进制位址400开始的一级代码页表
Maybe you want DMA on your 16-bit system.Who knows?The first few pages are reserved for hardware flags, etc.
也许可以在16位系统中使用直接存储器存取,随便吧 前几页必须留给硬碟分区
Assume page-table entries have eight status bits.The eight status bits would then be...Anybody?
如果页表项有八个状态位 会是哪八个呢… 谁来回答?
And I see we have our first surrender.Don't worry, Mr. Zuckerberg.Brighter men than you have tried and failed this class.
我看到了第一个逃兵 别灰心,扎克伯格先生 比你聪明的人也没能答出来
One valid bit, one modified bit,one reference bit and five permission bits.That is correct.
1个有效位,1个修改位,1个参考位5个权限位 回答正确
Does everybody see how he got there?Mark?You Mark Zuckerberg? Yeah.Cameron Winklevoss. Hi.Tyler Winklevoss.
有谁知道这是怎么运算出来的吗?马克?你是马克扎克伯格? 对 卡梅伦文克莱沃斯 嗨 泰勒文克莱沃斯
Are you guys related?That's good. Funny.We never heard that before.
你们是亲戚?很有眼力 有意思 还没人这么问过
So, what can I do for you?Did I insult your girlfriends?No. You didn't. Actually, I don't know.
找我什么事,来替女朋友出头? 不是,不知道怎么开口
Yeah, we never asked. We should do that. No.We have an idea we want to talk to you about.
我们不太求人的 还是说吧 不是 我们有一个创意,想找你聊聊
You got a minute?You guys look like you spend some time at the gym.
有时间吗? 你们看上去练过几下子
We have to. Why? We row crew.Yeah I've got a minute. Great.So, you ever been inside the Porcellian? No.
我们必须得练 为什么?我们是赛艇队的 好,我跟你们走 太好了 你从没去过坡斯廉俱乐部吧? 没有
You understand we can't take you past the bike room,because you're not a member.I've heard.
我们只能安排你到门廊,希望你理解 因为你不是会员 我听说过