An Efficient Grid Scheduling Algorithm with Fault Tolerance and User Satisfaction

Algorithm 1

Bicriteria scheduling algorithm.

Step 1: Get the list of tasks submitted by the user with its user deadline UD𝑇_𝑖

Step 2: Construct ETC𝑇_𝑖,𝑅_𝑗 matrix of size 𝑚×𝑛 where 𝑚 represents the number of tasks

   and 𝑛 represents the number of resources involved.

Step 3: Construct RT𝑅_𝑗 matrix of size 1×𝑛.

Step 4: For each task 𝑇_𝑖 in the queue and for each resource 𝑅_𝑗 where 𝑗∈𝑛

   do

      Construct CT𝑇_𝑖,𝑅_𝑗 matrix of size 𝑚×𝑛

      Construct CMT𝑇_𝑖,𝑅_𝑗 matrix of size 𝑚×𝑛

      Construct TCT𝑇_𝑖,𝑅_𝑗 matrix of size 𝑚×𝑛

      Compute Failure rate FR𝑅_𝑗∀𝑗∈𝑛

      Create a list UD𝑇_𝑖 for each task 𝑇_𝑖 with resources which has TCT𝑇_𝑖,𝑅_𝑗≤UD𝑇_𝑖

      If entries in UD𝑇_𝑖,

         select the resource with minimum FR𝑅_𝑗 and Set task 𝑇_𝑖, Resource 𝑅_𝑗, and

         TCT𝑇_𝑖,𝑅_𝑗 to CANDIDATE𝑇_𝑖,𝑅_𝑗,TCT𝑇_𝑖,𝑅_𝑗

      else

         Construct Diff𝑇_𝑖=TCT𝑇_𝑖,𝑅_𝑗−UD𝑇_𝑖

         Compute Fitness Value FV𝑇_𝑖,𝑅_𝑗=FFR+𝐹_Diff

         Set task 𝑇_𝑖, Resource 𝑅_𝑗 with lowest fitness value and their TCT𝑇_𝑖,𝑅_𝑗 to

         CANDIDATE𝑇_𝑖,𝑅_𝑗,TCT𝑇_𝑖,𝑅_𝑗

      endif

      Choose task 𝑇_min with minimum TCT𝑇_𝑖,𝑅_𝑗 from CANDIDATE𝑇_𝑖,𝑅_𝑗,𝑇𝐶𝑇𝑇_𝑖,𝑅_𝑗

      Dispatch task 𝑇_min to Resource 𝑅_𝑗 and remove 𝑇_min from task list.

      Update RT(𝑅_𝑗) where 𝑗 is the resource to which the task 𝑇_min is dispatched.

      Update FR𝑅_𝑗, if resource 𝑅_𝑗 fails, where 𝑗 is the resource to which the task 𝑇_min

      is dispatched.

   done

Step 5: If there are tasks in Task_list,

      Repeat step 4.

   else

     Compute Makespan=maxRT𝑅_𝑗 and

      HitRate=𝑇_succ/𝑇_sub∀𝑗∈𝑛

      where

         𝑇_succ is the number of tasks successfully completed by a resource 𝑅_𝑗

           without any failure and

      Deadline hit = number of tasks successfully completed within deadline.

   endif