Thank you !<br>I will try kmap/kunmap later.<br><br><br><div class="gmail_quote">On Fri, Nov 11, 2011 at 4:20 PM, Dave Hylands <span dir="ltr"><<a href="mailto:dhylands@gmail.com">dhylands@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Hi Geraint,<br>
<div class="im"><br>
On Thu, Nov 10, 2011 at 8:44 PM, Geraint Yang <<a href="mailto:geraint0923@gmail.com">geraint0923@gmail.com</a>> wrote:<br>
> Hi Dave,<br>
> Thank you for your help !<br>
> Does it mean that I could use all of the memory my computer has? But one of<br>
> my classmates told me that kernel could only use 1G from a 4G<br>
> memory.computer...Is there anything I have misunderstood ?<br>
<br>
</div>There is a certain amount (exact amount depends on the architecture<br>
and configuration) that can be accessed directly all of the time.<br>
<br>
Then there is high memory, which can be accessed using kmap/kunmap.<br>
See <a href="http://linux-mm.org/HighMemory" target="_blank">http://linux-mm.org/HighMemory</a><br>
<br>
If you have a 64-bit system, then you can access all of the memory directly.<br>
<div class="HOEnZb"><div class="h5"><br>
--<br>
Dave Hylands<br>
Shuswap, BC, Canada<br>
<a href="http://www.davehylands.com" target="_blank">http://www.davehylands.com</a><br>
</div></div></blockquote></div><br><br clear="all"><br>-- <br><div style="text-align:left">Geraint Yang <br>Tsinghua University Department of Computer Science and Technology</div>
<div><br></div><br>