At its heart, CMOD is a DB2 application.
There are two operating system parms that I'm aware of to benefit DB2.
I'm not going to go into detail on them as they're easily google-able.
1. USEZOSV1R9RULES(NO)
Set via your DIAGxx.
Can also be implemented dynamically with a SET DIAG=xx command.
To see if you have this enabled use the operator command D DIAG
D DIAG
IGV007I 12.36.01 DIAG DISPLAY
...
VSM USEZOSV1R9RULES(NO)
...
2. MEMDSENQMGMT: ENABLE
Set via your ALLOCxx
Can also be implemented dynamically using SETALLOC SYSTEM,MEMDSENQMGMT=ENABLE
To see if you have it enabled use the operator command D ALLOC,OPTIONS
D ALLOC,OPTIONS
IEFA003I 13.19.40 ALLOC OPTIONS
SPACE foo
UNIT foo
TIOT foo
SDSN_WAIT foo
VOLUME_ENQ foo
VOLUME_MNT foo
SPEC_WAIT foo
ALLC_OFFLN foo
CATLG_ERR foo
2DGT_EXPDT foo
VERIFY_VOL foo
SYSTEM foo
MEMDSENQMGMT: ENABLE
Note: if implementing dynamically I believe you need to bring up DB2 after the parms are set.
I have no benchmarks, sorry.
Ed