Table 5-5 Two-way classic IRWW that uses RELEASE(COMMIT) ITR and CPU time When running the classic IRWW workload in a two-way data sharing environment, the effects  of the data sharing overhead that is triggered by introducing inter-Db2 read/write interest can  be observed. When comparing the measurement results of the same migration step between  the one-way (see Table 5-2 on page 160) and two-way (see Table 5-5) data sharing tests, the  data sharing overhead is evident and reflected in an increase in Total CPU/Commit time and  reduction of the ITR per Db2 member. However, the benefits of the fast index traversal feature are not diminished when comparing  the two-way to the one-way data sharing group measurements.  The distributed IRWW workload is the main workload that is used to evaluate Db2 12’s  performance capabilities in distributed environments. The workload includes the following  transactions: Each of these transactions issues SQL statements to simulate the same set of business  functions, as described in A.3, “IRWW distributed workload” on page 379. The test environment that was used to run these workloads used the following configuration: GLYPH<SM590000> JCC driver 3.66.33, JDK 1.7.0, IBM J9 VM (build 2.6, JRE 1.7.0 Linux s390x-64  20121024_126071). GLYPH<SM590000> A Linux on System z on a z13 LPAR with three general CPs with Db2 Connect and Db2 for  Linux, UNIX, and Windows 10.5 (s130428). GLYPH<SM590000> A z13 z/OS LPAR with 3 dedicated general CPs and 32 GB of memory that used z/OS 2.2. 162  IBM Db2 12 for z/OS Performance Topics GLYPH<SM590000> SQCL: CLI (dynamic) that uses Db2 Connect GLYPH<SM590000> JDBC: JDBC (dynamic) that uses JCC T4 driver GLYPH<SM590000> SQLJ: Static Java that uses JCC T4 driver GLYPH<SM590000> SPCB: Stored procedures in COBOL (static) that uses Db2 Connect GLYPH<SM590000> SPSJ: Stored procedures in SQLJ (static) that uses JCC T4 driver GLYPH<SM590000> SPNS: Stored procedures in native SQL (static) that uses JCC T4 driver GLYPH<SM590000> SP500: Total of 500 stored procedures in native SQL (static) that uses JCC T4 driver 5.3 Distributed IRWW workload performance measurements Classic IRWW measurement Average ITR  (commits/sec)  per member Total CPU/commit  (microseconds) per  member Db2 12 vs. Db2 11  CPU/commit  (delta %) Baseline: Db2 11 NFM 3584 653 N/A Db2 V12R1M100 (FTB Auto)  No rebind 3635 629 -3.7 Db2 V12R1M100 (FTB Auto)  After rebind 3548 621 -4.8 Db2 V12R1M500 (FTB Disabled)  No additional rebind 3672 622 -4.7 Db2 V12R1M500 (FTB Auto) No additional rebind 3725 607 -7.0