有關top命令中的%st，sar命令中的%steal

轉載自：http://blog.csdn.net/yui/article/details/6395033

譯文（可能翻譯得不是很流利，將就着看吧，實在看不懂了能夠看下面的原文）

 

st 的全稱是 Steal Time ，就是 Xen Hypervisor 分配給運行在其它虛擬機上的任務的實際 CPU 時間。

 

IBM 關於 steal time 的定義至關好：

 

%st(Steal time) 是當 hypervisor 服務另外一個虛擬處理器的時候，虛擬 CPU 等待實際 CPU 的時間的百分比。

 

那麼，這到底是什麼意思呢？

 

Steal 值比較高的話，你須要向主機供應商申請擴容虛擬機。服務器上的另外一個虛擬機可能擁有更大更多的 CPU 時間片，你可能須要申請升級以與之競爭。另外，高 steal 值可能意味着主機供應商在服務器上過量地出售虛擬機。若是升級了虛擬機， steal 值仍是不降的話，你應該尋找另外一家服務供應商。

 

低 steal 值意味着你的應用程序在目前的虛擬機上運做良好。由於你的虛擬機不會常常地爲了 CPU 時間與其它虛擬機激烈競爭，你的虛擬機會更快地響應。這一點也暗示了，你的主機供應商沒有過量地出售虛擬服務，絕對是一件好事情。

 

原文及原文地址： http://www.91linux.com/html/article/cmd/top/20090417/16525.html

 

st, It turns out that this stands for 'Steal Time' and is the amount of real cpu that the Xen Hypervisor has allocated to tasks other than running your Virtual Machine.

 

IBM's definition of steal time is actually pretty good:

 

Steal time is the percentage of time a virtual CPU waits for a real CPU while the hypervisor is servicing another virtual processor.

 

So, relatively speaking, what does this mean?

 

A high steal percentage may mean that you may be outgrowing your virtual machine with your hosting company. Other virtual machines may have a larger slice of the CPU’s time and you may need to ask for an upgrade in order to compete. Also, a high steal percentage may mean that your hosting company is overselling virtual machines on your particular server. If you upgrade your virtual machine and your steal percentage doesn’t drop, you may want to seek another provider.