Difference Between SAP_ALL and SAP_NEW

What is the difference between SAP_ALL and SAP_NEW

Definition of SAP_NEW:-
SAP_NEW is a SAP standard Profile which is usually assigned to system users temporarily during an upgrade to ensure that the activities and operations of SAP users is not hindered, during the Upgrade. It contains all the necessary objects and transactions for the users to continue their work during the upgrade. It should be withdrawn once all upgrade activities is completed, and replaced with the now modified Roles as it has extensive authorizations than required.

Definition of SAP_ALL:-
SAP_ALL is a SAP standard profile, which is used on need basis, to resolve particular issues which may arise during the usage of SAP. It is used by Administrators/Developers only and is applied on a need to use basis, then withdrawn. It contains all SAP system objects and Transactions. SAP_ALL is very critical and only SAP* contains SAP_ALL attached to it in the production system. No other dialog users have SAP_ALL attached to them.

SAP_NEW is used in the Production environment during a version upgrade whereas SAP_ALL shouldn't be or not allowed be used in Production (for audit purposes obviously), except where necessary, in a controlled manner with all proper approvals from the customer.

SAPOSCOL - SAP Operating System Collector

what is saposcol?
A)SAPOSCOL is SAP Operating System Collector
is a standalone program that runs in background at OS level. It
collects information about operatin system resource usage like

• CPU Utilization
• Main Memory and Virtual Memory utilization.
• Physical Disk and File System utilization.
• Resource usage by running processes.

How many instances of SAPOSCOL to be run?
A)Only
one instance of SAPOSCOL needed to be run per hardware. Even if there
are multiple instances running on a single hardware only one SAPOSCOL
process is needed.

What is the frequency of data collection by SAPOSCOL?
A) Data is collected every ten seconds.

Where is the data collected by SAPOSCOL stored?
A)The data is stored in shared memory and for long & future usage data is stored in tables MONI & OSMON.
    Tha data collected by SAPOSCOL copied to tables MONI & OSMON by background job COLLECTOR_FOR_PERFMONITOR

What are the SAP level tcodes to view this data?
A) At SAP level you can view the information collected by SAPOSCOL using tcodes/transactions ST06, OS06 & OS07.

What is Heap Memory?

Heap Memory stores User Context when Extended Memory allocated to a work process gets exhausted and the work process requires more space to continue. Heap Memory stores contains same type of Data as Extended Memory. Heap Memory is allocated dynamically according to requirement and not during system startup. When the workprocess starts using heap area it enters in to PRIV mode.

Important categories of Profile Parameters in SAP

These are important categories of system parameters. You can access and change them using RZ11.
to
display you can use report RSPFPAR which can be run thorough SA38. Not
all parameters can be changed.Using RZ10 (profile maintainance) 
you can change parameters that are dynamically switchable and they are
activated immediately.

• ES/* : Related to extended memory settings
• INSTANCE* : Identify an instance or server
• ABAP/* : Related to program execution, including heap settings
• AUTH/* : Related to authorization
• DBS/<DB Type/* : Database specific parameters
• EM/* : General system related settings
• ENQUE/* : Settings for the enqueue WP (or standalone ENQ server)
• GW/* : SAP Gateway related settings
• ICF/* & ICM/* : Settings for the Internet control framework and ICM
• LOGIN/* : Controls the logon environment (such a multiple sessions etc)
• MS/* : Message server related settings
• RDISP/* : Controls the dispatcher & dispatcher controlled processes
• STAT/* : Statistics collector related parameters
• SCSA/* : Shared common system area parameters
• ZTTA/* : Extended memory related parameters

Tcode SM50

Tcode SM50.
Sm50
tcode is used to see the workprocess overview in application
server you are logged in.
There are several fields diplayed in the work
process overview screen.
Each of the field value is described in below
table.


Menu path for this tcode is
 Tools --> Administration--> Monitor -->System monitoring --> Process --> overview

No	This is the work process number and is unique to each work process.
Type	This denotes the type of work process. These are the possible values for type field DIA: Dialog UPD: Update BGD: Background ENQ: Enqueue SPO: Spool
PID	Process ID which is a unique no to identify the process at os level.
Status	This shows the status of work process like PRIV mode etc..
Ended	Work process has been terminated because of some error in SAP kernel. Running – work process is busy processing user request.    Waiting – work process is ready to accept user request. PRIV – Work process running with heap memory (noramally basis admins terminate the dia wp if it enters priv mode).
Completed	The work process has been terminated and they can not be restarted.
Reason	If a work process status is stopped, this field gives the reason why it is stopped.
Start	This field tells if the dispatcher can restart the work process if it gets terminated.
Err	Err field gives the no of times the work process .
Sem	Number of semaphore. With Green background =>Process is holding the semaphore. With Red background => Process is waiting for the semaphore.
CPU	The CPU Time utilization by each work process format minutes:seconds
Time	The time that has been consumed processing the current request (in seconds).
Report	The name of report which is being executed
Clie	Client No.
User	Name of user whose request is currently being executed.
Action	For the work process with status “running”, this displays the current action.
Table	The DB tables that is accessed previously by work process.

Profile Parameters Related to Memory in SAP

Instance Profile Parameters Related to Memory

abap/heaplimit	Work Process Restart
ztta/roll_extension	Limit for Extended Memory
ztta/roll_extension_dia	EM Quota for Dialog Work Processes
ztta/roll_extension_nondia	EM Quota for Non-Dialog Work Processes
abap/heap_area_dia	Heap Memory Limit for Dialog Work Processes
abap/heap_area_nondia	Heap Memory Limit for Non-Dialog Work Processes
abap/heap_area_total	Total Quota for Heap Memory
ztta/roll_area	Size of Roll Area Roll Area
ztta/roll_first	Size of the Initial Allocation from the Roll Area
abap/heap_area_total	Heap Memory Limit
em/initial_size_MB	Extended Memory Pool Size
rdisp/ROLL_SHM	Roll Buffer Size
rdisp/ROLL_MAXFS	Maximum Roll File Size
rdisp/PG_SHM	Size of the Paging Buffer
rdisp/PG_MAXFS	Maximum Size of SAP Paging File
em/blocksize_KB	Segment Size for the Extended Memory Memory Management Statistics
em/stat_log_size_MB	Statistics - User Context Size
em/stat_log_timeout	Statistics - User Context Size

Operation modes in SAP

Using the operation modes, you can adjust the type and distribution of the
work processes to the varying load distribution during the day. You can
also adjust the distribution of the work processes to business
requirements that only occur once. During the day the demand for dialog
work process is high an system response for dialog work process must be
fast. At night there are less users so system resources are not
utilized fully if a major percent of them is reserved for dialog work
process. By defining operation modes, you can change not only the total
number of work processes defined in the profiles, but also the type and
distribution of the individual work process types within this total
number. The switch between the work process types is performed
dynamically during the runtime of the SAP system. The switch is
triggered using a defined schedule. A reserved work process is not
immediately terminated, but marked for switching. This means that
certain delays may occur. This type change is logged in the system log.
During the switch of the operation modes, neither the instance nor the
affected work processes need to be restarted. This means that the
quality of the buffer of the SAP system is retained during an operation
mode switch ,and that the request that is currently being processed by
a work process is completed. The individual work processes retain their
process ID after the switch, which can be observed in the process
overview (SM50).You can trigger an operation mode switch from a program
that you have written yourself using a function module (RZL_PERFORM_BA_SWITCH)

Memory allocation of non-dialog work process in UNIX & Windows

Memory allocation of non-dialog work process in UNIX

In UNIX, if Roll memory gets full Heap memory is occupied and if heap memory gets full extended memory is used.

But
in windows it is different, after roll memory (ztta/roll_first) is
filled the work process uses Extended memory, after extended memory is
fill then remainder of roll memory ( ztta/roll_area - ztta/roll_first)
is used soon..

Unix or Unix like systems	Windows
Roll Memory up to  ztta/roll_area	Roll Memory up to ztta/roll_first
| | \|/	| | \|/
Heap Memory  up to abap/heap_area_nondia or HM Exhaust	Extended Memory up to ztta/roll_extension or EM Exhaust
| | \|/	| | \|/
Extended Memory up to ztta/roll_extension or EM Exhaust	Roll Memory Remainder of ztta/roll_area
	| | \|/
	Heap Memory up to abap/heap_area_dia or HM Exhaust

Different types of Locks in SAP

Why object locks?
The locks are used in sap to prevent concomitant change of an object by two developer.

The
enque work process manages the locking system. The lock entries for data to be
processed in lock table which is maintained in main memory.


Various Lock Modes in SAP

Shared Lock (S):
                              Several
users can access the locked data at the same time in display mode.
Requests for further shared locks are accepted, even if they are from
other users. Exclusive locks are rejected.

Exclusive lock (E):
                                 The
locked data can be displayed or edited by one user only. Requests for
either another exclusive lock or a shared lock are rejected.


Optimistic Lock (O):
   

              
          An optimistic lock
can be set if the data is displayed in change mode and the lock behaves
like a shared lock if there are access collisions. But if the data is
changed, the optimistic lock converts to an exclusive lock. 0ptimistic
locks on the object then become invalidated. It can therefore be
possible that the conversion fails, if beforehand another optimistic
lock was converted. In such cases the use of optimistic locks is only
beneficial, if the probability that the data will NOT be changed is
high.

Exclusive but not cumulative lock (X):
   
           
           

        Exclusive but not cumulative
locks can only be requested by the same transaction once only. All
further lock requests are rejected.

Some Q&A about dispatcher

What is dispatcher?
A) Dispatcher is tha central workprocess in an application server which along with operating system manages the resources for ABAP applications.

What does the dispatcher does?
A) The dispatcher distributes the transaction load among various work process, connecting to the presentation level and organizing communication. The processing requests are first saved in request queues and then processed according to 'first in -- first out' rule.

Does Dispatcher process data?
A) No, the data is processed in work process like dialog wp or background wp or update wp etc.. The dispatcher only distributes load between work process. There is no assignment of a work process to single user. The requests which are created by user using SAPGUI is distributed among the work process. Processing user requests sometimes requires data to be read from the database or written to it. For this, every work process is connected directly to the database.

How do you check the status of a job

One can check the status of a background job in tcode sm37 (job overview). You can see the job status of all jobs of a userid by entering the userid in the job selection screen or you can see the status of jobs by selecting naming convention. you will have options in the sm37 screen to select jobs by their status.

What are the different status of background jobs

There are 6 status for background jobs

• Scheduled - The job has been created, but it has not yet been assigned a starting time.
• Released - The job has been created and it has been assigned a starting time.
• Ready - The job is ready to be processed.
• Active - The job is being processed.
• Finished - The job has finished successfully.
• Cancelled - The job did not finish successfully.

Memory Allocation sequence for Dialog Work Process in Windows and Unix

memory allocation for dialog work process
This is the order in
which the memory space is used. If Roll memory is filled then the
memory in Extended memory is used and soon as shown below. The memory
allocation sequence is same in windows & unix.

Roll Memory (Max size) ztta/roll_first	------->	Extended Memory up to ztta/roll_extension or EM Exhaust	-----------+             |            \|/
			Roll Memory Remainder of ztta/roll_area
			|            \|/
			Heap Memory up to abap/heap_area_dia or HM Exhaust

ztta/roll_first	maximum size of Roll memory
ztta/roll_extension	max size of extended memory
ztta/roll_area	max size of local roll area
abap/heap_area_dia	max size of heap memory

Composite Roles

Composite Roles :-
                        Suppose there is position in your organization in which activites of two positions need to be performs the roles is called composite role.
                         Take an example. There are two positions like a clerk and auditor. If there is a position in your organization where the individual has to act both as a clerk and an auditor the the role is a composite roles which needs him/her to work both as a clerk and auditor. This is quite common scenario in organizations or companies.
A composite role has many single roles. No authorization data can be maintained in a composite role.  You can eneter some menu entries like links to websites, reports only. Tcodes cannot be added. The authorization data has to be maintained only in the single roles.
                         When you attach a composite roles to an user all the single roles gets attached to him. In the change documents it shows the single profiles that belongs to single roles gets attached to them. Suppose a composite role has 3 single roles. when you attach this composite role to a user then 3 authorizations profiles will get attached to him. The change count  in SUIM will be 3.

Roles in SAP

What is a authorization Role in SAP?
                        Role is the way how authorizations are granted in SAP or the activities which are performed by and individual are restricted. A role consists of all the duties performed by an individual in the organization. For e.g., the clerk or the manager or buyer or dispatcher etc.. Two managers of same cader has same type of duties. Technically a roles contains all the items(transactions or tcodes, reports, links) which are needed by an individual in particular position. In a  roles-based authorization system the lattice structure of organization is well defined and the activities performed by each individual is defined clearly. In a role-based authorization system the users are assigned to generiuc roles (technical)  which contains tcodes necessary for peforming the job. The above description is a single role.
                     
                        There are three types of roles.

• Single roles
• Composite roles
• Derived roles

Typical types of system in SAP Landscape

Types of systems available in SAP land scape. The following are the typical systems which are available in a SAP Landscape. They can be very complex SAP land scapes. The standard R/3 lanscape consists of Development , QA and a Production system.

• sandbox/play ground
• training or education
• development or build
• System Test/QA
• Migration or Regression Testing
• Production System

Regression or migration system

Regression or migration system in SAP Landscape
For example if you are going to upgrade form ECC4.6C to ECC 6 then upgrade is first performed on this system and after successful upgradation the same is implemented on production system.

Copied from Production (on request) to support regression testing with productive data

• Make Regression testing secure as well as thorough and meaningful by using production end-user profiles and production representative data
• Supports testing of conversion and cutover activities
• No changes are permitted in this environment
• This system can serve as a System Test/QA environment

Quality System

 Quality System of SAP Land Scape
Testing and validation of all changes introduced in the Development System during the Design and Build Phase. In this system the authorizations are to be restricted. Every program which is developed in development ssytem is tested on sample data present in the QA system and only if the program passes all the tests then it is transported to production system.

• All correction necessitated by the testing need to be done in the Development environment and retested in the System Test environment
• No Changes can be permitted in the System Test/QA environment
• The testing carried out can be Functional Test, Integration Test, User Acceptance testing
• This system can also serve as the Training environment

Development System

Development System in SAP LandScape
All Design and Build will be carried out in this system. This is one of the critical systems in the landscape. One need to be careful because the change made in the development would be transported into production unknowingly. This is the system where developers develop their programs or tcodes or reports and transport them to production  and QA

• First Round of testing of all designed and built objects will be carried out in this system
• This system will always be the “Original System” for all the changes introduced during the implementation
• All changes introduced during implementation will be distributed from this system to other SAP systems in landscape
• No Design and Build is normally permitted in any system in the Landscape other than the Development system
• This system may, in certain cases, serve as the Sandbox as well as QA system (though this is not the SAP recommended strategy)

Sandbox System

Sand box system in SAP Landscape
An isolated environment, i.e. changes made in the sandbox would never flow to the implementation landscape
This is the system where normally people play. do R&D and gain knowledge bcos they can do anything and experiment in this system.

• Used to carry out preliminary analysis
• Can be used to prototype design & build
• Will be re-created several times during a SAP project lifecycle (like a sand sculpture)
• The Sandbox system will mostly be re-build from the Development System
• Since this system can be recreated any time no changes are taken out from this system to any other systems in the landscape