Difference between revisions of "Talk:Containers/Guarantees for resources"

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(Created page with 'Hi, I guess limiting is only useful when there's enough room for all groups. Eg.: the calculation makes sense only if: <code>(1) ∀ i: Li >= Gi</code> Otherwise, the gro…')
 
 
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Hi,
 
Hi,
I guess limiting is only useful when there's enough room for all groups. Eg.: the calculation makes sense only if:  
+
I guess limiting is only useful when there's enough room for all groups. Eg.: the calculation will make sense only if:  
  
 
<code>(1) &forall; i: Li >= Gi</code>
 
<code>(1) &forall; i: Li >= Gi</code>
  
Otherwise, the group limit is to strict.Obviously it's required that:
+
Otherwise, the group limit is too strict.Obviously it's required that:
  
 
<code>(2) &sum; Gi <= R </code>
 
<code>(2) &sum; Gi <= R </code>
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, and the above condition is enough:
 
, and the above condition is enough:
  
<code>(3) L1 = (1/N-1) * ((R-G2)+(R-G3)+...+(R-Gn) - (N-2)*(R-G1)) > G1 </code>
+
<code>(3) L1 = (1/N-1) * ((R-G2)+(R-G3)+...+(R-Gn) - (N-2)*(R-G1)) >= G1 </code>
  
 
&hArr;
 
&hArr;
  
<code>(4) ((R-G2)+(R-G3)+...+(R-Gn) - (N-2)*(R-G1)) > (N-1)*G1</code>
+
<code>(4) ((R-G2)+(R-G3)+...+(R-Gn) - (N-2)*(R-G1)) >= (N-1)*G1</code>
  
 
&hArr;
 
&hArr;
  
<code>(5) (N-1)*R-(G2+G3+...+Gn)-(N-2)*R+(N-2)*G1 > (N-1)*G1</code>
+
<code>(5) (N-1)*R-(G2+G3+...+Gn)-(N-2)*R+(N-2)*G1 >= (N-1)*G1</code>
  
 
&hArr;
 
&hArr;
  
<code>(6) R - (G2+G3+...+Gn) + (N-2)*G1 > (N-1)*G1</code>
+
<code>(6) R - (G2+G3+...+Gn) + (N-2)*G1 >= (N-1)*G1</code>
  
 
&hArr;
 
&hArr;
  
<code>(7) R > G2+G3+...+Gn+G1</code>
+
<code>(7) R >= G2+G3+...+Gn+G1</code>
  
Thus limiting is only useful if the trivial condition under (2) holds.
+
Thus limiting is only useful if the natural condition under (2) holds.
  
 
Cheers,
 
Cheers,
  
 
Gyula
 
Gyula

Latest revision as of 05:25, 7 May 2010

Hi, I guess limiting is only useful when there's enough room for all groups. Eg.: the calculation will make sense only if:

(1) ∀ i: Li >= Gi

Otherwise, the group limit is too strict.Obviously it's required that:

(2) ∑ Gi <= R

, and the above condition is enough:

(3) L1 = (1/N-1) * ((R-G2)+(R-G3)+...+(R-Gn) - (N-2)*(R-G1)) >= G1

(4) ((R-G2)+(R-G3)+...+(R-Gn) - (N-2)*(R-G1)) >= (N-1)*G1

(5) (N-1)*R-(G2+G3+...+Gn)-(N-2)*R+(N-2)*G1 >= (N-1)*G1

(6) R - (G2+G3+...+Gn) + (N-2)*G1 >= (N-1)*G1

(7) R >= G2+G3+...+Gn+G1

Thus limiting is only useful if the natural condition under (2) holds.

Cheers,

Gyula