What tcode can I used to find out how much memory is
allocated to R/3 in total? I know for Oracle I can get the SGA memory. I am
using SAP 4.7 / Oracle 9i on Unix AIX.
Go to ST02 --> Detailed analysis --> Sap memory. This
will let you know memory allocated for that app server. You can also find out
memory allocated for user (mode list) and Quotas.
You can also use report RSMEMORY to find out how sap
alloctes memory to Dia and Non Dia work processes.
I'm afraid that is incorrect. The question is also not
a simple answer.
Go to ST02 --> Detailed analysis --> Storage is the
correct path. The Virtual memory allocated line shows SAP's allocated memory.
This memory does not include what the DB uses or the OS
or other things running on the server. More importantly it does not include heap
(private memory) allocated by WP's. It also does not include the executable size
of the GW, the ICM and the dispatcher but it does include most of their memory
in the shared memory areas.
It also does not allow for additional memory that a
Windows system may dynamically allocate to extended memory if the users use it
all up.
Question on Shared Memory and IMODE
Can someone tell me about Shared memory (Code
Definition) and IMODE? I have never heard these terms in SAP R/3, Shared momey
sounds like its related to Operating System.
All memory is OS memory I'm afraid there is little
distinction in that regard.
Shared memory is memory that can be addressed by
different processes as opposed to private memory that can only be addressed by
the process that creates it. A good examlpe would be the Program Buffer (PXA)
this buffer hold the recently used programs in memory for fast access and needs
to be read by all work processes. A more impotrant shared memory area is
extended memory. In 32 bit processing you need to keep shared memory areas at a
minimum because otherwise you limit the amount of space in the address space
that your program can use for its own data. I won't get into a sad chat about
all this bat thats hared memory.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
An IMODE is an internal mode. An example may be best,
log onto a SAP system, create a new session and leave one at the main menu and
with the other go to ST02. In ST02 near the bottom of the screen double click on
the extended memory line. In the next screen click on the Mode List button. You
will see you have the ST02 session marked with an X for being attached and
another session in IMODE 0.
With the other session got to SM36 then swap back to
ST02, press enter and you will see the session has an IMODE 0 and an IMODE 1
use. Now from the SM36 screen click on the button Job Selection and jump back to
St02 and press enter, you will see the session has an imode 0 1 and 2 active.
Imode 0 is not really an IMOde but the main mode that
all your information relevant in any transaction is available. As you call
transactions inside transactions you need new memory and the old stuff needs to
be save for when you green arrow back. This is why you have imodes so that when
you green arrow back from the job selection screen above (I mode2) it is no
longer the active mode and imode 1 is reactivated.
