Better control of STACK and HEAP allocation in CICS.

We want better control of the AUTODST parameter behaviour in CICS.

We want to be able to control the maximum initial and incremental sizes.

We also want to be able to control the percentage of the expected total sizes that goes to initial and incremental sizes.

I.e.

AUTODST=(YES,20,10,5M,3M,10,10,10M,4M)

YES => Auto tuning is on.

20    => Percentage of the measured total STACK size to be allocated for the initial STACK

10    => Percentage of the measured total STACK size to be allocated for the STACK increments

5M   => Maximum amount of storage that AUTODST can calculate for initial STACK  size

3M   => Maximum amount of storage that AUTODST can calculate for incremental STACK  size

10      => Percentage of the measured total HEAP size to be allocated for the initial HEAP

10      => Percentage of the measured total HEAP size to be allocated for the HEAP increments

10M  => Maximum amount of storage that  AUTODST can calculate for initial HEAP  size

4M     => Maximum amount of storage that AUTODST can calculate for incremental HEAP  size

The Minimum sizes should taken from the Language Environment runtime options.

Examples:

if AUTODST have found the an enclave has a total stack size of 50mb and heap size of 100Mb, the actual sizes would be

In the examples we assume that we have

HEAP=((128K,64K,ANYWHERE,KEEP,4K,4080),OVR),  

STACK=((128K,64K,ANYWHERE,KEEP,4K,4080),OVR)

20% of 50mb=10mb, maximum initial stack 5mb                                  => Initial stack 5mb.

10% of 50mb=5mb,   maximum incremental stack 3mb                    => Increamental stack 3mb

10% of 50mb=5mb                                                                                                     => Initial heap 5mb

10% of 50mb=5mb maximum incremental heap 4mb                        => Increamental heap 5mb

if AUTODST have found the an enclave have a toal stack size of 20mb and heap size of 1Mb, the actual sizes would be

20% of 20mb=4mb,                                                                                                    => Initial stack 4mb.

10% of 20mb=2mb,                                                                                                    => Increamental stack 2mb

10% of 1mb=102k,                                                                                                      => Initial heap should be taken from LE-runtime options =>128K

10% of 10mb=102k                                                                                                   => Increamental heap 102K

This should be applicable for the HEAP and STACK in 31-bit storage.

The calculated sizes should be rounded up to nearest 4k boundary.

For larger extents(>500K) it may also be desireable to round to nearest 1mb boundary. This could be applicable when using TRANISO=YES.