Analysis of the ALL_OBS SAS Data Set
The final step of the job class identification process involves some decisions based on the cluster descriptions and the analyst's experience.
micsrm140
Although the clusters developed in the example provide an excellent representation of the system's workload, there are too many clusters to define a job class structure with a class for each structure. Providing a minimum number of alternative job classes would simplify the job class selection process. Therefore, after analyzing the data from the cluster centroids and the population statistics reports (see Figures 11-26 and 11-28 in Cluster Centroids Report - Batch Job Class), we proposed four job classes. These classes are shown in the following table.
CLUSTERS CLASS JOBMXNTA JOBTCBTM JOBNLR REPRESENTED ===== ======== ======== ======== ============= 1 0 5 2000 7 2 0 60 5000 2,4,9,6 3 >=1, <=2 60 20000 1,3,5,8,10,11 4 unlim unlim unlim outliers
A SAS program was written to evaluate the proposed classes. The program attempts to assign each job to the classes (tested in ascending order of size) until a match is found. The results from the execution of this program are shown in Figure 11-29.
As you can see in the figure, 10,722, 4,155, 1,489, and 2,267 jobs fell into the four classes. These values correspond to 58, 22, 8, and 12%, respectively, of the system's workload. To test the sensitivity of these job class limits, we should repeat the analysis varying the job class limits by + or -5%. If the results of these analyses do not significantly change the percentage of the workload represented by each of the classes (that is, more than 2 or 3% of the jobs change classes), then you can be confident that none of the job classes bisect a resource consumption pattern in the workload.
Figure 11-29. Sample ALL_OBS Analysis Program
1 DATA _NULL_; 2 SET JOBFILE.ALL_OBS END=EOF_SW; 3 RETAIN C1 C2 C3 C4 0; 4 5 IF JOBMXNTA<=0 & JOBTCBTM<=05 & JOBNLR<=02000 THEN DO; 6 C1+1; 7 GO TO T_EOF; 8 END; 9 IF JOBMXNTA<=0 & JOBTCBTM<=60 & JOBNLR<=05000 THEN DO; 10 C2+1; 11 GO TO T_EOF; 12 END; 13 IF JOBMXNTA>=1 & JOBMXTAP<=2 & JOBTCBTM<=60 & JOBNLR<=20000 THEN DO; 14 C3+1; 15 GO TO T_EOF; 16 END; 17 C4+1; 18 T_EOF: 19 IF EOF_SW THEN DO; 20 PUT C1= / C2=/ C3=/ C4=; 21 P1=C1/(C1+C2+C3+C4)*100; 22 PUT P1=; 23 P2=C2/(C1+C2+C3+C4)*100; 24 PUT P2=; 25 P3=C3/(C1+C2+C3+C4)*100; 26 PUT P3=; 27 P4=C4/(C1+C2+C3+C4)*100; 28 PUT P4=; 29 END; C1=10722 C2=4155 C3=1489 C4=2267 P1=57.45 P2=22.30 P3=7.99 P4=12.17 NOTE: THE DATA STATEMENT USED 1.76 SECONDS AND 384K. 30 RUN; NOTE: SAS USED 384K MEMORY. NOTE: SAS INSTITUTE INC. SAS CIRCLE BOX 8000 CARY, N.C. 27511-8000