Performance numbers were collected and compared between AOT, DGTT, and PBG being  the insert targeting tables.  A dedicated z13 LPAR with six CPs and a full rack Mako machine were used to evaluate the  performance of AOT. All of the tables that the queries reference were accelerated. For the  DGTT and PBG cases, the accelerator returned data to Db2 to insert. For the AOT case, the  accelerator inserted returning data directly into the AOT on the accelerator side.  The results are shown in Figure 10-1. Queries RI101 ~ RI104 are complex selects with a few returned rows for insert. Queries  RI101 ~ RI104 contain different subselect statement. Little performance difference was  observed among AOT, DGTT, and PBG as most time was spent at query in IDAA. Queries RI201 ~ RI210 are simple selects with many rows returned for insert. The advantage  of using AOT to insert directly is significant (up to 163X between AOT and DGTT, and 267X  between AOT and PBG). We exhausted the work file space in Db2 subsystem in RI208 for  DGTT scenario and did not continue the query.  Queries RI301 ~ RI303 are simple selects with 1 million returned rows of 16, 32, and 48  columns respectively. Again, AOT shows the benefit.  Queries RI401 ~ RI403 are simple selects with 1 million returned rows of the same number of  columns of integer, char or varchar, and date columns, respectively. When AOTs are used as the target of insert from select, the select and insert parts were run  on the accelerator. Almost no CPU cost was left on Db2 side. These experiments demonstrate the benefit of the use of AOT when more than 300,000 rows  are processed.  304  IBM Db2 12 for z/OS Performance Topics Figure 10-1 Insert with subselect with AOT, DGTT, PBG as insert target table AOT AOT DGTT PBG CL2EL CL2EL DGTT/AOT CL2EL PBG/AOT CL2CPU CL2CPU CL2CPU 5 RI101 102.00 103.83 1.02 103.07 1.01 0.01 0.08 0.02 2 RI102 90.31 90.13 1.00 90.33 1.00 0.01 0.01 0.01 175 RI103 286.21 286.33 1.00 284.89 1.00 0.01 0.01 0.01 4,200 RI104 3.63 4.38 1.21 3.21 0.88 0.01 0.03 0.03 340,000 RI201 1.83 2.29 1.26 3.57 1.95 0.00 1.18 1.93 3,400,000 RI202 11.57 21.65 1.87 29.85 2.58 0.00 11.71 16.64 1,200,000 RI203 3.58 7.96 2.22 9.04 2.52 0.00 4.52 6.23 12,000,000 RI204 13.21 71.89 5.44 76.12 5.76 0.00 47.58 53.96 1,000,000 RI205 1.58 5.04 3.19 9.55 6.05 0.00 4.38 5.87 10,000,000 RI206 3.48 46.90 13.46 63.16 18.13 0.00 44.00 48.26 100,000,000 RI207 27.16 462.35 17.02 673.99 24.82 0.00 437.70 567.32 1,000,000,000 RI208 290.58 canceled 14863.80 51.15 0.00 canceled 13879.28 180,000,000 RI209 8.94 851.74 95.29 1291.38 144.47 0.00 801.85 1191.08 180,000,000 RI210 5.15 843.07 163.80 1377.73 267.68 0.00 794.80 1186.29 1,000,000 RI301 1.56 5.04 3.23 9.57 6.13 0.00 4.43 5.93 1,000,000 RI302 2.34 7.65 3.27 12.90 5.52 0.00 5.65 7.18 1,000,000 RI303 2.76 10.72 3.88 15.38 5.57 0.00 6.89 8.67 1,000,000 RI401 0.88 4.12 4.68 7.98 9.07 0.00 3.47 5.29 1,000,000 RI402 1.22 4.54 3.72 9.24 7.57 0.00 3.91 5.41 1,000,000 RI403 0.90 4.63 5.13 8.41 9.32 0.00 4.16 5.96 Sum 858.90 18943.18 22.06 0.07 16995.36 #Rows CORR Remarks small # rows  for insert large # rows  for insert,  RI210 source  is AOT different #  columns - 16,  32, 48 different data  types - INT,  CHAR, DATE DGTT PBG Elapsed time comparison (unit is second) CPU time comparison (unit is second)