About extend memory used in ST02

Question

Dear expert
Is there a way to know how extend memory is used in ST02
When system start,no user log on we can see:
SAP Memory      Curr.Use % CurUse[KB] MaxUse[KB]
Extended memory     1.95  122，880  208,800
But we can find ,after user log on,the extend memory wiill increased.
SAP Memory      Curr.Use % CurUse[KB] MaxUse[KB]
Extended memory     54.92  3,452,928  3,768,320
I checked sm04 and stad,no such large amout of memory used.
We can see the problem in  Y55.
Is there any way to know how the extend memory is used?
Thank you very much for your help.
Best Regards,
Ellen Wang
Active Global Support - Technology
SAP Asia Pacific(GMT+8)

Answer 1

The value specifies the size of the roll area in bytes.The roll area is one of several memory areas from which the memory
requirements of user programs are satisfied.For technical reasons, approximately the first 250 KB of a user context is always
stored in the roll area, additional data
1) to the limit ztta/roll_first in the roll area, then
2) in extended memory, to the limit ztta/roll_extension    or, if extended memory is exhausted, then
3) in the roll area again, until the roll area is full, then
4) in the heap memory (PRIV mode), to the limit    abap/heap_area_dia or abap/heap_area_total or until    the address space or
the swap space is exhausted.
Tthe case of non-dialog work processes, the sequence 1) 3) 4) 2) applies. After this, terminations occur, with errors such as:
STORAGE_PARAMETERS_WRONG_SET or an error code that indicates a memory bottleneck.
Cheers !
Manish