Figure 5-18 Journal table insert external throughput rate This test scenario simulates a message queue management application. The Db2 table is  treated as a queue. A task inserts some rows sequentially into this queue table, while it also  starts to process and delete rows at the front of the queue table. This scenario features the  following configuration: The CPU time results that are shown in Figure 5-19 show a Db2 class 2 CPU time  improvement of 6% for the one-way and two-way benchmarks in Db2 12 compared to Db2 11.  Log write latch contention (LC19) removal and buffer manager timer latch (LC23) removal are  the biggest contributors to the class 2 CPU time reduction. 5.6.3 Message queue insert and delete GLYPH<SM590000> A PBG table space  GLYPH<SM590000> Row level locking GLYPH<SM590000> Multi-row insert with 10 rows per commit GLYPH<SM590000> A one-way and two-way Db2 data sharing group Figure 5-19 Message queue insert and delete SAP 1-way and 2-way Class 2 CPU time Chapter 5. Workload level measurements  183