The measurement results of our tests are listed in Table 3-1. The allocated LFAREA that was  used during both measurements was the same. There were 68,009 1 MB frames allocated in  the run that used 1 MB frames (EXP_1M), while 33 2 GB and 425 1 MB frames were used  during the run that used 2 GB frames (EXP_2G). The results showed 33 * 2048*1 MB +  425*1 MB frames = 68,009 1 MB frames allocated; therefore, an equal number of storage was  used as LFAREA in both cases. Table 3-1 Z13 1MB versus 2 GB frame measurement results Measurement ID 1 MB Frame size  (EXP_1M) 2 GB Frame size (EXP_2G) Delta  (EXP_2G/EXP_1M) CPU 2964(z13) 2964(z13) # General CPs 12 12 z/OS z/OS 2.1 z/OS 2.1 LFAREA allocated 2 GB pages = 0 1 MB pages = 68009 2 GB pages = 33 1 MB pages = 425 Db2 V11 PTF (07/22/2015) V11 PTF (07/22/2015) Workload ETR (commits/sec.) 5055.523 5052.434 CPU (%) 60.98 59.91 ITR (commits/sec.) 8290.461 8433.374 +1.7% CPU time (MBps/commit) Class 2 CPU 1.176 1.130 MSTR 0.005 0.004 DBM1 0.013 0.012 IRLM 0.003 0.003 Total Db2 CPU  (member scope) 1.197 1.149 -4.0% Although this measurement is not Db2 12 specific and was performed by using a Db2 11  environment, you can expect similar results when Db2 12 on a z13 is used with 2 GB page  frames. The IEASYSxx LFAREA keyword specifies the amount of real storage to be made available  for 1 MB and 2 GB large frames. All 1 MB and 2 GB frames are backed by contiguous 4 KB  real storage frames, and are allocated from real storage as specified by the LFAREA  keyword, as shown in the following example: LFAREA=(1M=88064,2G=40) As a result of this command, 88,064 1 MB frames and 40 2 GB frames (166 GB real storage)  are allocated in the LFAREA at IBM MVS™ IPL time. 108  IBM Db2 12 for z/OS Performance Topics 3.4.2 Usage guidance and considerations