Coarse-Grain QoS-Aware Dynamic Instance Provisioning for Interactive Workload in the Cloud

Algorithm 2

The instance provisioning algorithm.

Input: VP_table;

Output: 𝑘_𝑖,𝑖∈{0,…,𝑁}; {𝑘₀ is the number of RIS instance, and 𝑘_𝑖,𝑖≠0 is the number

of MIS instance in phase 𝑖.}

(1) for  𝑖=1 to 𝑁  do

(2)  for  𝑗= MIN_NUM to MAX_NUM do

(3)   if VP_table[𝑖][𝑗] ≤𝑥 and VP_table[𝑖][𝑗+1] ≥𝑥  then

(4)    𝐾_𝑖=𝑗+1;

(5)    break;

(6)   end if

(7)  end for

(8) end for

(9) 𝑘₀=0;

(10) 𝑚=𝑁×𝐶_𝐿×𝑘₀+∑^𝑁_𝑖=1[𝐾_𝑖−𝑘₀]⁺×𝐶_𝑆;

(11) for  𝑖=1 to 𝑁  do

(12)  𝑗=𝐾_𝑖;

(13)  temp=𝑁×𝐶_𝐿×𝑗+∑^𝑁_𝑖=1[𝐾_𝑖−𝑗]⁺×𝐶_𝑆;

(14)  if  temp<𝑚  then

(15)   𝑘₀=𝑗;

(16)  end if

(17) end for

(18) for  𝑖=1 to 𝑁  do

(19)  𝑘_𝑖=𝐾_𝑖−𝑘₀;

(20) end for