In reply to:
Why do I ask you about "who the user root is" and "what the command sh is" ?
Because I found out that sometimes it will spent many cpu resource when the administrative user root using the command sh.
check these figures
I don't think the root "sh" process is relevant to your problem. I feel resentful explaining simple unix/linux concepts to you because I feel as though you should take the time to study this on your own rather than just keep asking questions that people keep telling you aren't relevant to your problem.
In reply to:
you can see the used cpu resource from figures 1 , 2, 3, and 4.
(figure 1) before I reboot the server
http://img138.imageshack.us/img138/4797/62914232hy9.png
(figure 2) when I reboot the server
http://img338.imageshack.us/img338/4508/14441331ez0.png
(figure 3) after I reboot the server, the used cpu usage decrease at once.
http://img138.imageshack.us/img138/2629/17010317gk2.png
(figure 4)
http://img138.imageshack.us/img138/1236/99699604az9.png
It's not relevant to your problem. It's a lower priority process running as part of some other basic part of the server. Who knows what it is? For all we know, it could be the equivalent of the odd "idle" process that you see under windows.
In reply to:
(3) from may 21 till now, about the site down, I only get the following infomation from DH support team.
========================================================================
DreamHost Customer Support Team
If you want your server to be up, you'll need to reduce the amount of
memory you're using, OR, add more.
========================================================================
It's perfectly understandable that it's all they responded if it's true, and from your server memory and cpu logs, it's true.
In reply to:
but now my problem is that when the server down, whether I reboot server or readjust the amount of
memory , the server still down, it can't be re-started again. it didn't work.
So you've been slowly adjusting the amount of memory up and your server still goes down? Have you considered installing some kind of limiter on your forum to prevent too many people from using it at the same time? This will, at least, allow you to see where the problem lies.
In reply to:
(4)
my questions are in the figure
http://img380.imageshack.us/img380/9396/58213636jz3.png
Those problems aren't caused by the root sh process.
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