Scheduling Parallel Jobs Using Migration and Consolidation in the Cloud

Algorithm 1

FCFS with KEASY backfilling and consolidation.

  input : 𝐽_fg: jobs running in fg VMs;

     𝐽_bg: jobs running in bg VMs;

     𝐽_𝑞:  jobs waiting in the queue.

(1) begin

(2)  /^*Step 1:  Schedule runnable jobs according to FCFS ^*/

(3)  sort 𝐽_𝑞∪𝐽_bg according to job arrival time;

(4)  for  𝑒𝑎𝑐ℎ𝑗𝑜𝑏𝑗𝑖𝑛𝐽_𝑞∪𝐽_bg   do

(5)     𝑁_𝑗 ← process number of 𝑗; 𝑁_idle ← idle fg VM number;

(6)     if  𝑁_𝑗>𝑁_idle  then

(7)    break;

(8)     else

(9)      If Deploy (j, 'K')   then

(10)        remove 𝑗 from 𝐽_𝑞 or 𝐽_bg, insert it into 𝐽_fg;

(11)  if   𝐽_𝑞∪𝐽_bg   is empty  then

(12)    return;

(13)  /^*Step 2:  Make reservation for the first job in 𝐽_𝑞∪𝐽_bg, then backfill^*/

(14)  let 𝑇_𝑆 = 0 (shadow time), 𝑁_𝐸 = 0 (extra fg VM number);

(15)  𝐻𝑑𝐽𝑜𝑏 ← first job in 𝐽_𝑞∪𝐽_bg; 𝑁_𝑅 ← process number of 𝐻𝑑𝐽𝑜𝑏;

(16)  𝑁_future ← current idle fg VM number;

(17)  Sort 𝐽_fg in ascending order of their termination time;

(18)   for each job j in the sorted 𝐽_fg   do

(19)     𝑁_𝑗 ← processe number in 𝑗; 𝑁_future=𝑁_future+𝑁_𝑗;

(20)     if  𝑁_future≥𝑁_𝑅   then

(21)      𝑇_𝑆 = the termination time of 𝑗; 𝑁_𝐸 = 𝑁_future − 𝑁_𝑅; break;

(22)  /^* Backfill runnable jobs^*/

(23)   for each job 𝑗 in 𝐽_𝑞∪𝐽_bg   do

(24)     𝑁_𝑗 ← processe number of 𝑗; 𝑁_idle ← idle fg VM number;

(25)     if   𝑁_𝑗>𝑁_idle   then

(26)      continue;

(27)     𝑡_𝑟 ← the runtime of 𝑗; 𝑡_𝑐 ← current time;

(28)     if (𝑡_𝑟+𝑡_𝑐≤𝑇_𝑆) or 𝑁_𝑗≤𝑁_𝐸   then

(29)       if Deploy (j, 'K') then

(30)      remove 𝑗 from 𝐽_𝑞 or 𝐽_bg, insert it into 𝐽_fg;

(31)      if   𝑡_𝑟+𝑡_𝑐>𝑇_𝑆   then

(32)      𝑁_𝐸 = 𝑁_𝐸 − 𝑁_𝑗;

(33)  /^*Step 3:  Try to deploy jobs to the background tier^*/

(34)  sort 𝐽_𝑞 in ascending order of their runtime;

(35)  for each job 𝑗 in the sorted 𝐽_𝑞   do

(36)     𝑁_𝑗 ← processe number of 𝑗; 𝑁^𝑏_idle ← idle bg VM number;

(37)     if   𝑁_𝑗 ≤ 𝑁^𝑏_idle   then

(38)     Dispatch('BG',𝑗);